• The United States has demonstrated its ability to deal substantial military defeats to jihadist groups that take territory. Yet jihadist groups remain a resilient threat, forcing a discussion of U.S. objectives and aims in its counterterrorism wars.
• Over the past year, the United States and its partners have successfully eliminated almost all of ISIS’ territorial holdings in Syria and Iraq.
  • ISIS lost its capital, Raqqa, in October 2017 and the last Iraqi town it held in November 2017.
  • The United Nations reports that ISIS has lost all of the urban areas it held in Iraq and Syria.
  • In July 2018, the coalition stated that ISIS held only 300 square kilometers of territory.
  • ISIS’ territorial losses undercut its ability to train and organize terrorist attacks as well as its claim to be the caliphate, traditionally understood as a territorial entity.
  • ISIS’ territorial losses over the past year reflect a pattern that began under the Obama administration.
• ISIS has also continued to face substantial personnel and leadership losses as a result of coalition operations.
• ISIS’ propaganda apparatus has deteriorated under military and other forms of pressure.
  • The apparatus is increasingly decentralized.
  • Multiple studies have found a declining level of propaganda output, and key parts of the propaganda apparatus, including the Rumiyah magazine, appear to have ceased publication.
  • ISIS has made multiple blatantly false claims of responsibility in recent years, including claiming an attack by an indebted gambler in the Philippines and the Las Vegas shooting by Stephen Paddock, despite no evidence of any ISIS role.
• Despite these setbacks, ISIS will likely pose a resilient threat.
  • ISIS continues to hold a small amount of territory, and efforts to retake that territory have been disrupted by a flare-up in the conflict between Turkey and the Kurds.
  • ISIS continues to operate as a guerrilla and terrorist organization. In January 2018, ISIS conducted bombings in Baghdad killing more than two dozen people, and in July 2018 it killed more than 200 people in a raid on Syrian government-held territory.
  • Unresolved governance issues in Iraq and Syria provide fertile ground for jihadists to exploit to stage a resurgence, though the potential for such a resurgence in Iraq should not be overestimated.
  • ISIS’ affiliates will continue to pose their own threat, though they will also face the constraints of U.S. and partner military force. Both of these dynamics were seen in ISIS’ seizure and loss of the Philippine city of Marawi and the fragmentation of ISIS in Libya.
  • ISIS’ virtual networks will likely continue to inspire and organize attacks and provide support for foreign fighter travel in the case of a new fighter flow.
• Al-Qaeda remains a resilient and persistent threat in the Middle East and North Africa. And despite its poor track record on this front in recent years, an al-Qaeda attack in the West cannot be ruled out.
• Regardless of the fate of particular organizations, the Middle East and North Africa remain the site of political and economic instability, likely ensuring a resilient jihadist movement for the foreseeable future.
• Saudi Crown Prince Mohammad bin Salman’s reform project offers the potential for important positive gains in the effort against jihadism. The impact of the reforms is unclear, but they warrant close attention as they will likely shape the nature of the jihadist threat in coming years.
• Policymakers should also be wary of the potential for an escalation in the Saudi-Iran proxy war or the U.S.-Iran tension that could fuel apocalypticism and benefit jihadism in the region on a scale similar to the aftermath of the 2003 Iraq invasion.
• The Trump administration has reportedly loosened restrictions on drone strikes and the United States’ counterterrorism wars. The administration’s policy changes reportedly include:
  • Transferring the authority to approve strikes to combatant commands.
  • Eliminating the requirement for a target to pose an “imminent threat.”
  • Moving some authority to conduct strikes from the military back to the CIA, where strikes can be covert.
• The Trump administration has backtracked on transparency regarding the U.S. counterterrorism wars, making the extent and impact of these changes difficult to assess.
  • The administration has not released its new policy guidance that replaced the Obama-era Presidential Policy Guidance regarding counterterrorism strikes.
  • The administration has ignored an Obama-era executive order requiring a yearly update on casualties in U.S. counterterrorism strikes.
• The Trump administration has substantially escalated the U.S. drone wars in Yemen and Somalia.
  • In Yemen, the United States conducted 131 counterterrorism strikes in 2017, according to CENTCOM — more than twice the previous peak. There have been 41 strikes in 2018 as of the end of August, according to New America’s research.
  • In Somalia, the United States conducted an unprecedented 34 strikes in 2017 and 21 strikes so far in 2018 as of the end of August, according to New America’s research.
  • However, strikes were already escalating in Yemen and Somalia under the Obama administration, according to New America’s research.
• In contrast, in Pakistan and Libya, the Trump administration has been more restrained in conducting strikes.
  • In 2017, the Trump administration ended a nine-month pause in strikes in Pakistan, but conducted only eight strikes in 2017 and five in 2018 as of the end of August, according to New America’s research, a rate similar to the last years of the Obama administration and far below the peak of the campaign.
  • In 2016, the United States conducted 510 strikes in Libya, mostly aimed at ISIS in the area around Sirte. The war deescalated under the Trump administration with 17 strikes in 2017 and only five strikes in 2018 as of the end of August.
• The jihadist terrorist threat to the United States is relatively limited.
  • Jihadists have killed 104 people in the United States since 9/11. Every one of these deaths is a tragedy. They do not, however, represent the kind of strategic failure that occurred on 9/11. The death toll is far below what many analysts expected after the 9/11 attacks.
  • Neither al-Qaeda, ISIS nor any other foreign terrorist organization has directed a terrorist attack inside the United States since 9/11.
• The number of jihadist terrorism cases in the United States has declined consistently and substantially since 2015, when an unprecedented 80 people were either charged with crimes or died before being charged, compared with only eight people in 2018 as of the end of August.
• ISIS’ losses constrain its ability to target the United States. However, because the threat to the United States was almost entirely from ISIS-inspired or ISIS-enabled attacks rather than ISIS-directed attacks, policymakers should not expect a fundamental shift in the threat as a result of ISIS’ losses. The October 2017 truck ramming attack in Manhattan illustrates the potential for continued attacks.
• The United States is protected by its enormous investment in both defensive and offensive counterterrorism efforts, and it is a much harder target than it was on 9/11.
• The most likely threat to the United States remains attacks inspired or enabled but not directed by ISIS.
• ISIS has executed a successful effort to inspire and organize jihadist violence in the United States.
  • Since 2014, the year ISIS declared its caliphate, 83 people have been killed in jihadist attacks, three-fourths of all deaths in such attacks since 9/11.
  • Since 2014, there have been eight deadly attacks in the United States (seven of which were inspired in part by ISIS), and 12 nonlethal jihadist attacks.
• Despite this threat, caution should be exercised in attributing the attacks solely to jihadist ideology. Many of the attackers had personal issues including histories of nonpolitical violence and mental health problems, and some appear to have been influenced by multiple ideologies and not just jihadism.
• The threat to the United States is almost entirely homegrown. Just under half of jihadist extremists charged in the U.S. were born citizens and 84 percent are citizens or legal permanent residents. About three in ten are converts to Islam.
• The travel ban would not have prevented a single deadly attack since 9/11 nor would it have prevented the 9/11 attacks.
• Jihadists are not the only threat to the United States. Far-right extremists have killed 73 people since 9/11 and have conducted six deadly attacks since the beginning of the Trump administration alone.
• Europe faces a far more severe threat than the United States. Since 2014, it has seen five attacks directed by ISIS that killed 188 people, more than have been killed in any type of jihadist attack inside the United States since 9/11.
• The threat to Europe may be turning the corner.
  • The last attack directed by ISIS core occurred in March 2016, and the last attack by an affiliate was the May 2017 Manchester bombing directed by ISIS in Libya.
  • The number of attacks grew through 2017, driven by an increase in ISIS-inspired attacks, but appears to have declined so far in 2018.
• However, the threat to Europe is elevated compared to the United States due to the large number of European foreign fighters and returnees, the greater size and more established nature of European jihadist networks, the failure of Europe to integrate its Muslim population, rising conflict driven in part by immigration and the growth of anti-immigrant right-wing populism, and Europe’s geographic proximity to conflict zones in North Africa and the Middle East.
• Terrorism will likely be shaped by several key trends in the near future. These include:
  • The use of TATP explosives in particular by attackers with close ties to ISIS or other more organized groups.
  • The rise and increasing popularity of vehicular ramming as a terrorist tactic and the expansion of its current popularity to those not motivated by jihadism.
  • The use of armed drones by terrorist organizations, as demonstrated by ISIS, the Houthi rebels and a variety of other groups.
  • Aviation as a continued focus of jihadist terrorists, being a potential route for groups to conduct mass-casualty attacks while avoiding many of the difficulties of organizing terrorism inside the United States or other Western countries.
  • The continued absence of chemical, biological, radiological or nuclear attacks in the West by jihadists and the reliance upon lower-technology forms of weaponry like vehicular ramming, explosives and firearms. Recent jihadist plots involving ricin and chemical agents require attention to the potential threat, however.
  • The coming release of large numbers of individuals convicted of terrorism-related crimes both in Europe and the United States, and often inadequate efforts to reintegrate them.

Given the state of the threat, we recommend the following:

• The president and his National Security Council should release a public counterterrorism strategy.
• The United States should conduct an assessment and audit of the amount of money spent on counterterrorism efforts since the 9/11 attacks.
• Congress should debate and pass a new Authorization for Use of Military Force (AUMF).
• The White House should draft and publicly release a report detailing the Trump administration’s policies regarding counterterrorism strikes similar to the Presidential Policy Guidance released by the Obama administration in 2016.
• The Pentagon should provide a public accounting of the countries where the United States is conducting counterterrorism operations and better communicate the existence and role of such operations to legislators and the public. Congress should uphold its responsibility to pay attention to where and why the U.S. is engaged in military action.
• Congress should expand oversight of U.S. counterterrorism strikes and the Pentagon should expand protections against civilian casualties.
• The United States should seek to deescalate conflicts in the Middle East and North Africa.
• The president should end the travel ban.
• The United States government should build trust with rather than alienate Muslim communities.
• The United States should relentlessly hammer home the message that while ISIS has positioned itself as the defender of Muslims, its victims are overwhelmingly Muslim.
• The United States should conduct a review and assessment of alternatives to prison time for convicted jihadists, efforts to prevent radicalization in prison, and the state of preparations for release for those convicted of terrorism-related crimes.

The United States has demonstrated its ability to deal substantial military defeats to jihadist¹ groups that take territory and thus to constrain jihadist activity. The almost total territorial defeat of the Islamic State in Iraq and Syria (ISIS)² in the past year illustrates this. Yet groups, including ISIS and al-Qaeda, remain resilient, and instability in the Middle East, North Africa and parts of South Asia makes it extremely unlikely that even the defeat of any particular group will end the jihadist threat in those regions.

These conditions suggest the need for foundational evaluation of U.S. goals in its counterterrorism wars, and what is achievable at what cost. Under the Trump administration, the United States has escalated many of these wars and backtracked on the already limited transparency provided regarding them. Assessing the true impact of the Trump administration’s policy changes is difficult in this environment. The scale of the strategic and moral questions that surround the wars requires a more transparent and open discussion.

Over the past year, the United States and its partners have successfully eliminated almost all of ISIS’ territorial holdings in Iraq and Syria. In October 2017, the American-backed Syrian Democratic Forces (SDF) liberated Raqqa, the capital of ISIS’ self-proclaimed caliphate, from ISIS control.³ In November, Iraqi forces retook the last town under ISIS control in Iraq.⁴ In early 2018, the United Nations Security Council Committee Analytical Support and Sanctions Monitoring Team reported that ISIS “lost control over all remaining urban areas [in Iraq and Syria].”⁵ In April 2018, Col. Ryan Dillon, the spokesman for the counter-ISIS coalition, stated that the group had lost more than 90 percent of the territory it had captured in Iraq and Syria.⁶ In July 2018, the coalition stated that ISIS held only 300 square kilometers of territory in Syria.⁷

The loss of its territory in Iraq and Syria dramatically undercuts ISIS’ claim that it is the caliphate, because the caliphate has historically been a substantial geographic entity, such as the Ottoman Empire, as well as a theological construct.⁸

ISIS’ territorial defeat over the past year reflects a pattern of retreat since September 2014, when the United States commenced airstrikes against the group in the wake of the murder of American journalists held hostage. By September 2016, ISIS had lost key Iraqi cities including Baiji, Fallujah, Ramadi and Tikrit, as well as the Syrian city of Manbij.⁹

The coalition successfully retook eastern Mosul from ISIS in January 2017.¹⁰ In August 2017 Brett McGurk, the U.S. special presidential envoy for the Global Coalition to Defeat ISIS, estimated that ISIS had ceded operational control in 78 percent of its territory in Iraq and 58 percent of what it controlled in Syria.¹¹

The loss of its territory in Iraq and Syria dramatically undercuts ISIS’ claim that it is the caliphate.

While ISIS’ territorial collapse has been significant, it is important not to exaggerate its extent. ISIS continues to hold small patches of territory. On May 1, 2018, SDF officials noted, “ISIS retains a significant presence near the Iraqi borders from which it seeks to retain safe haven to plan attacks around the world and expand its territory in Syria and Iraq.”¹² ISIS also continues to operate with guerrilla actions in northern Iraq.¹³

Alongside its territorial losses, ISIS has lost many of its key leaders and fighters more generally. According to Gen. Tony Thomas, commander of the U.S. Special Operations Command, as of July 2017 the coalition had killed between 60,000 and 70,000 ISIS fighters.¹⁴

Among the key leaders and operatives killed or captured in the past year:

• Abu Abdel al-Haq: Abu Abdel al-Haq, who had been head of ISIS’ internal security, was arrested in May 2018 as a result of a sting operation.¹⁵
• Salim Benghalem: In November 2017, Salim Benghalem, a French foreign fighter accused of plotting the 2015 Paris attacks and having links to the Charlie Hebdo attackers and Mehdi Nemmouche, who conducted an attack in Brussels in 2014, was killed in an airstrike in Syria, according to family members of his.¹⁶
• Abu Khattab al-Iraqi: On May 26, 2018, Abu Khattab al-Iraqi, who according to the coalition led ISIS’ oil and gas network, was killed during coalition operations in Syria along with three other figures involved in the network.¹⁷
• Tarek Khayat: In early 2018, Tarek Khayat was arrested in Iraq. Khayat provided direction and support to a plot to bomb a flight from Sydney, Australia, according to Australian officials.¹⁸ The plot was a highly sophisticated enabled plot involving the shipping of bomb materials from Turkey.
• Saddam al–Jammel: Saddam al-Jammel, who had been in charge of ISIS’ territory around Deir al-Zour, was arrested as a result of the same sting operation involving Abdel al-Haq in May 2018.¹⁹
• Alexanda Kotey and El Shafee Elsheikh: Alexanda Kotey and El Shafee Elsheikh, two British militants who were part of the group known as “the Beatles” and who were involved in the murder of Western hostages held by ISIS, were captured by U.S.-backed Kurdish forces in January 2018.²⁰ Kotey reportedly had helped enable a foiled attack plot in Britain via online communication.²¹

ISIS leadership losses over the past year built upon substantial losses in earlier years, including Turki al-Binali, ISIS’ top religious authority; Abu Muhammad al-Adnani, who was ISIS’ emir in Syria, its principal spokesman, a key organizer of attacks on the West and a reputed possible replacement in the case of ISIS chief Abu Bakr al-Baghdadi’s death; Sami al-Jabouri, who led ISIS’ oil exploitation effort; and Omar al-Shishani, a prominent Chechen ISIS commander.²²

ISIS’ propaganda effort has also suffered setbacks. Key propaganda outputs including ISIS’ English-language magazine Rumiyah appear to have ceased publication.²³ According to the United Nations Sanctions Monitoring Team, “the propaganda machinery of the ISIL core is further decentralizing, and the quality of its material continues to decline.”²⁴ Of particular note, ISIS has claimed a series of attacks that it had no connection to over the past couple of years.²⁵ For example, ISIS claimed an attack at a casino in the Philippines to which it had no connection and appears to have been committed by an indebted gambler; falsely claimed to have placed a bomb at Charles de Gaulle Airport in France; and claimed to be behind the mass shooting in Las Vegas by Stephen Paddock, a claim for which there is absolutely not a shred of evidence.²⁶ Other sources have similarly reported a decline in the extent of ISIS’ propaganda activity.²⁷

ISIS has claimed a series of attacks that it had no connection to over the past couple of years.

While ISIS’ retreat continued in 2018, four challenges caution against overoptimism regarding the swift defeat of the group.

1. Resilience as a Terrorist Organization: A foundational challenge to the defeat of ISIS is the group’s proven ability to continue operating as a resilient terrorist organization even after territorial defeats. On January 15, 2018, ISIS conducted suicide bombings in an eastern Baghdad market, killing more than two dozen people and demonstrating its continued ability to conduct terrorist attacks.²⁸ In July 2018, ISIS killed more than 200 people in a coordinated assault on Syrian government-held territory.²⁹ In 2017, the Combating Terrorism Center at West Point reviewed more than 1,400 ISIS attacks in 16 cities that had been liberated from ISIS — 11 in Iraq and five in Syria — and found that while taking territory back from ISIS was a positive development, “pushing the Islamic State out as the formal governing party in a territory is not a sufficient development when it comes to ending the group’s ability to enact violence against individuals in Iraq and Syria.”³⁰ This is not a new phenomenon. In 2011, New America fellow Brian Fishman noted that while casualties in Iraq’s civil war had declined overall during the successes of the surge, terrorism remained “rampant” and the Islamic State of Iraq — an al-Qaeda affiliate that later morphed into ISIS — remained capable of conducting major attacks.³¹
2. Unresolved Governance Failures and Conflicts: Another challenge is posed by the coalition’s failure to resolve an interlocking set of governance failures and conflicts in Iraq and Syria. ISIS was never the root of the security challenge, but a symptom of larger failures of governance.³² Beyond the difficult challenge of reasserting effective governance in areas previously held by ISIS, transregional conflicts and tensions — including the questions of Kurdish statehood, of Turkey’s role in the region and of a stable end-state for Syria, as well as Sunni-Shia sectarian tensions — will keep driving conflict. If the intertwined regional conflicts are not resolved, the United States and its allies may once again find themselves having won the battle only to lose in “Phase IV” reconstruction and stabilization efforts, as happened previously in Iraq.³³ This challenge was illustrated by the disruption to the campaign against ISIS that occurred when Turkey began bombing Kurdish forces in the northern Syrian city of Afrin.³⁴ In many ways, Iraq has exited the ISIS crisis in far better shape than conventional wisdom expected at the outset of the campaign.³⁵ In Syria, on the other hand, the failure to resolve governance challenges remains extensive and acute.
3. ISIS Affiliates: Another challenge is posed by ISIS’ affiliates outside of Syria and Iraq. The capture of the Philippine city of Marawi by ISIS-affiliated fighters in 2017 amid setbacks for ISIS in Syria and Iraq illustrates this challenge. The recapture of the city by the government illustrates the constraints on the ability of affiliates to resuscitate ISIS’ fortunes. Yet, despite losing its hold in Marawi, ISIS remains a threat in Southeast Asia and the impact of the battle on the local population remains significant.³⁶ Libya has also often been discussed as a potential fallback for ISIS, yet ISIS has been pushed out of the territory it had held there.³⁷ That said, the 2017 Manchester bombing, which was directed by ISIS in Libya, demonstrates the potential for ISIS to use its affiliates, even those that are themselves under pressure, to maintain its campaigns.
4. The Virtual Caliphate: A final challenge is posed by ISIS’ virtual networks — what some have termed a “Virtual Caliphate.” As Mitch Silber, former NYPD director of intelligence analysis, and Jesse Morton, the former leader and cofounder of the Salafi-jihadist group Revolution Muslim, noted in a report for New America, “[a] key lesson of the effort against Revolution Muslim is that countering virtual jihadist recruitment will be an ongoing struggle, and law enforcement and intelligence agencies should not overemphasize the collapse of any particular group.”³⁸ ISIS’ advances on the template for online jihadist organizing may allow it to maintain its strength even as it suffers territorial losses. Even if such activity doesn’t occur under the ISIS brand, such virtual networks will continue to pose a challenge for the future.

Even as ISIS suffers repeated setbacks, al-Qaeda has shown resiliency in the face of the counterterrorism campaigns directed against it and the challenge from within the jihadist movement posed by the rise of ISIS. In August, al-Qaeda marked the 30th anniversary of its founding, making the group one of the longest-lasting terrorist groups in history.³⁹

More than a decade and a half after 9/11, al-Qaeda continues to operate regionally despite the heavy losses it has sustained, including the death of its founder, Osama bin Laden, and of dozens of other al-Qaeda leaders killed in drone strikes in Pakistan and Yemen. Al-Qaeda in the Indian Subcontinent, Al-Qaeda in the Arabian Peninsula and Al-Qaeda in the Islamic Maghreb all retain capacity for sustained local attacks. As the then-director of the National Counterterrorism Center, Nicholas Rasmussen, explained at the July 2017 Aspen Security Forum, “Not a day goes by where al-Qaeda and the range of al-Qaeda threats we’re managing around the world is not top priority.”⁴⁰

In Syria, al-Qaeda’s fortunes are less clear, though any accounting must acknowledge a substantial al-Qaeda presence in the country. Al-Qaeda in Syria has undergone changes to its naming and organizational design. Initially known as the Nusra Front or Jabhat al-Nusra, al-Qaeda in Syria adopted the name Jabhat Fateh al-Sham in July 2016 to distance itself from al-Qaeda core, though then-Director of National Intelligence James Clapper labeled it a “PR move … to create the image of being more moderate.”⁴¹ In January 2017 another rebranding occurred, with the group taking the name Hayat Tahrir Al-Sham.⁴² Regardless of the shifting monikers, the group remained a potent force, as seen by its takeover of Idlib, a prominent city and province in the country’s northwest corner, in July 2017.⁴³ However, according to some analysts, the series of splits and rebrandings represents a meaningful loss of organizational control in Syria on the part of al-Qaeda and a major setback for the group.⁴⁴ Even so, al-Qaeda continues to count the loyalty of large numbers of fighters and to maintain a presence in Syria, demonstrating its resilience.

Even as ISIS suffers repeated setbacks, al-Qaeda has shown resiliency in the face of the counterterrorism campaigns directed against it.

While al-Qaeda has demonstrated its sustained ability to operate locally throughout the Middle East, North Africa and to some extent South Asia, its capability to strike the West is less clear. The last deadly attack in the West directed by al-Qaeda was the 2005 bombing of London’s transportation system, which killed 52 commuters. Al-Qaeda in the Arabian Peninsula, or AQAP, trained two brothers in Yemen in 2011 who more than three years later attacked the Paris offices of Charlie Hebdo, a satirical magazine.⁴⁵ It is far from clear if AQAP had any real role in directing this attack beyond providing training years before the attack took place.

Despite this poor record of success, al-Qaeda cannot be dismissed as a threat to the West. The lone-known American returnee from Syria to plot an attack in the United States, Abdirahman Sheik Mohamud, was directed to do so by and received training from al-Qaeda’s Syrian affiliate Jabhat al-Nusra, not ISIS.⁴⁶ The press release for his guilty plea states, “Mohamud planned to obtain weapons in order to kill military officers or other government employees or people in uniform.”⁴⁷ According to Nathan Sales, the U.S. State Department coordinator for counterterrorism, “AQAP retains the capability and intent to carry out external operations.”⁴⁸ In addition, although ISIS has dominated the branding of inspired attacks in the West, al-Qaeda’s brand — as opposed to that of ISIS — has been cited by a small number of attackers and plotters. For example, Tnuza Hassan, a 19-year-old U.S.-born citizen who was charged with setting a series of fires at St. Catherine University in Minnesota and attempting to provide material support to terrorists, specifically supported al-Qaeda, reportedly telling the FBI that she “was against ISIS” because “they are not part of the true caliphate. Al-Qaida is trying to create the true caliphate.”⁴⁹ In July 2018, Demetrius Pitts, a 48-year-old U.S.-born citizen, was charged with plotting an al-Qaeda attack after an undercover officer-driven investigation.⁵⁰

Al-Qaeda appears to be grooming one of Osama bin Laden’s sons, Hamza, to be a next-generation leader of the group. Hamza, in his late 20s, has long been an al-Qaeda true believer. In May 2017, al-Qaeda released audio in which Hamza called for attacks on the West.⁵¹ In March 2018, Hamza bin Laden appeared in a video where he discussed the U.S.-Saudi relationship.⁵²

Al-Qaeda’s resiliency and its preparation of a next-generation leadership raise the possibility that it could reemerge as a substantial threat to the West. It is also possible that al-Qaeda could feed off of ISIS’ setbacks to regain leadership of the global jihadist movement.⁵³ The possibility of parts of ISIS and al-Qaeda merging cannot be ruled out. At the very least, al-Qaeda’s ability to remain resilient after decades of counterterrorism efforts suggests that ISIS or at least its remnants may similarly be able to continue on long after losing its hold on much of Syria and Iraq.

Beyond the fates of particular organizations, whether al-Qaeda or ISIS, the jihadist movement has proven resilient in the Middle East, North Africa and South Asia in large part as a response to underlying stressors and continuing instability across these regions.

These underlying stressors include the Sunni-Shia sectarian conflict that overlaps with the Saudi-Iran regional proxy war playing out in Syria, Yemen and elsewhere; state collapse across the Middle East and North Africa, most extensively in Syria, Iraq, Yemen, and Libya; high unemployment and economic strain in much of the region; and an ongoing youth bulge.⁵⁴

This combination of factors, along with trends that reduce the barriers to entry to jihadist organizing including the rise of social media, make it likely that instability will continue in the Middle East and North Africa, and that this instability will enable jihadist activity in the region for the foreseeable future.

Instability will enable jihadist activity in the region for the foreseeable future.

The Arab Spring revolutions have passed for now, and while policymakers should remain attentive to the potential for surges of new revolutionary activity and how they might affect jihadist activity, two other region-shaping political dynamics are worthy of particular attention for their potential to fundamentally reshape the future of jihadist activity.

The first is the reform effort of Saudi Crown Prince Mohammed bin Salman. Bin Salman has announced a wide-ranging set of initiatives that include economic reforms, advances on women’s rights (including allowing women to drive) and an effort to control extremist religious ideology.⁵⁵ A successful reform effort that reduced the influence of extremist figures could have a profoundly positive effect on the jihadist threat. ISIS’ recruitment in the Arabian Peninsula was enabled and deeply shaped by the close relationships between elites in Saudi Arabia and neighboring countries and jihadists.⁵⁶ However, bin Salman’s reform effort is tied to his moves to consolidate personal power, which has resulted in the arrest of hundreds of prominent Saudis, purportedly as part of an anti-corruption drive, and their detention and alleged physical abuse.⁵⁷ In addition, the crown prince has played a key role in the pursuit of the disastrous war in Yemen, a potential risk to his consolidation of power.⁵⁸ Finally, even if implemented in a sustained and beneficial manner, bin Salman’s reforms could risk a backlash against liberalization that would benefit jihadists.⁵⁹

How bin Salman’s reform project will play out and its impact on jihadism is unclear. However, what is clear is that his effort is having a profound effect on politics in Saudi Arabia and the region that could redefine the jihadist threat and regional politics more broadly.

The second is the potential for the Saudi-Iran or U.S.-Iran proxy wars to escalate to full-scale war. As noted above, there is a Sunni-Shia conflict atop a Saudi-Iran proxy war playing out in many parts of the Middle East. While the consequences of a major escalation give strong reason for both Saudi Arabia and Iran to avoid direct confrontation and keep their conflict in the realm of proxies, a proliferation of flashpoints and the demonstrated ability of groups like Yemen’s Iran-backed Houthi rebels to strike inside Saudi Arabia pose the potential for an escalation to more direct conflict.⁶⁰ A major Saudi-Iran escalation would likely turn into an even broader regional conflict.⁶¹

In addition, the United States has reneged on the Iran nuclear deal, and the Trump administration has embraced a more escalatory tone toward Iran.⁶² Outright war remains unlikely but the risk of escalatory incidents between Iran and the U.S. is increasing, and the dangers cannot be ignored.

A major escalation in either of these conflicts would introduce fresh fuel for apocalypticism in the region and do so in a way that aligns with the jihadist ideology that has framed Iran and Shia Muslims as enemies; the consequences of a major escalation could be similar to the regional catastrophe generated by the 2003 U.S. invasion of Iraq.⁶³

In its first year, the Trump administration embarked upon a reshaping of U.S. policies regarding counterterrorism strikes. However, the extent and nature of these changes remains unclear as there has been little governmental transparency regarding counterterrorism operations under Trump, and what little is known comes from the news media.

During the presidential campaign, then-candidate Donald Trump made comments that suggested an interest in a radical expansion of American counterterrorism operations abroad and a loosening of restrictions regarding civilian casualties. For example, in December 2015, Trump called for the killing of terrorists’ families, saying, “The other thing with the terrorists is you have to take out their families,” while also criticizing the U.S. for “fighting a very politically correct war” against ISIS.⁶⁴

Upon taking office, the Trump administration began a review at senior levels of the National Security Council to roll back Obama-era restrictions on counterterrorism operations.⁶⁵ U.S. officials speaking to the Washington Post outlined the intentions of the review, describing it as an effort to “make it easier for the Pentagon to launch counterterrorism strikes anywhere in the world by lowering the threshold on acceptable civilian casualties and scaling back other constraints imposed by the Obama administration.”⁶⁶

Among these reported policy changes were:

• Transfer of operational authority from the White House to the Pentagon: In a February 2017 proposal to the president, Defense Secretary James Mattis recommended decreasing the decision-making time in the field by ceding tactical decisions to the Pentagon.⁶⁷ Trump obliged, giving autonomy to commanders to authorize strikes.
• Elimination of the “imminent threat” standard: The Trump administration in the summer of 2017 reportedly relaxed the Obama administration’s requirement that the target of strikes outside of war zones pose a “continuing and imminent threat” to Americans.⁶⁸ The administration has not publicly confirmed such a policy change. This reported change was preceded by the Trump administration’s approval of a series of requests to designate “areas of active hostilities,” which loosened such restrictions for specific geographic areas. Trump approved a Pentagon request to designate parts of three Yemeni provinces as “areas of active hostilities” early in his first year in office.⁶⁹ On March 29, 2017, Trump also designated the entirety of Somalia as an “area of active hostilities” for 180 days.⁷⁰
• Expanded Central Intelligence Agency paramilitary authority: The U.S. drone program began under the authority of the CIA. As the CIA is an intelligence organization, all of its paramilitary activities, including lethal operations such as drone strikes, are classified. After years of pressure, the Obama administration shifted the program, in part, to the Department of Defense in an effort to increase the drone program’s transparency. The military publicly reports airstrikes and resulting civilian casualties.⁷¹ In March 2017, in a departure from this Obama-era policy, Trump reportedly secretly granted the CIA new permissions to target and kill suspected militants, moving parts of the program back into the shadows.⁷²

Aside from policy changes, there is reason to believe that the Trump administration’s attitude toward counterterrorism operations and civilian casualties may also have influenced the conduct of strikes. In a worrisome sign potentially echoing his campaign rhetoric, while watching pre-recorded video of a drone strike where the CIA did not fire until the target had moved away from a house containing his family, Trump asked, “Why did you wait?” according to a report by the Washington Post.⁷³

In one of its first major counterterrorism operations, the Trump administration authorized a major ground raid in Yakla, Yemen, reportedly targeting Qasim al-Raymi, the leader of Al-Qaeda in the Arabian Peninsula. The raid resulted in at least 14 civilian deaths, including young children, and the death of Chief Petty Officer William Owens, a member of the Navy’s SEAL Team 6.⁷⁴

The Yakla raid illustrated the new aggressiveness. It was reportedly authorized over dinner following informal presentations from the chairman of the Joint Chiefs of Staff, Gen. Joseph Dunford, and Defense Secretary Mattis, whereas previous authorizations would have involved multiple formal processes for such a raid.⁷⁵ Trump confidants Steve Bannon and Jared Kushner were both reportedly at the dinner despite their lack of expertise and unclear security clearance statuses at the time.⁷⁶ On the other hand, there reportedly was no representation from the State Department, a departure from the previous norm.⁷⁷ Furthermore, according to reporting by NBC, then National Security Advisor Michael Flynn explicitly argued that the raid would be a “game changer” compared to President Obama’s deliberations and hesitancy to authorize strikes.⁷⁸

The Trump administration has also expanded the United States’ armed drone capability to Niger. The United States confirmed that armed drones had been deployed to the country to target militants in early 2018.⁷⁹

It is difficult to assess the nature and impact of the Trump administration’s policy and attitudinal changes regarding counterterrorism operations because of a lack of transparency regarding the new policy. The Trump administration has not released its new guidelines, which replaced the Obama administration’s Presidential Policy Guidance (PPG) on drone strikes. This is a step backward for transparency. In 2016, the Obama administration released the PPG, albeit toward the end of the president’s term, allowing for more public debate and discussion of America’s counterterrorism operations.⁸⁰

It is difficult to assess the nature and impact of the Trump administration’s changes because of a lack of transparency regarding the new policy.

Another warning sign regarding transparency is that the Trump administration decided to ignore an Obama-era executive order that required the administration to report the number of civilian and enemy casualties from American counterterrorism strikes, and was late in publishing a congressionally mandated summary of U.S. military operations that resulted in civilian deaths.⁸¹

While it is difficult to assess the extent and specific nature of policy and attitudinal changes regarding drone strikes under the Trump administration, reporting on the strikes that have occurred suggests that they have resulted in an unprecedented escalation of some of America’s counterterrorism wars during the administration’s first year. That escalation appears to have leveled off and perhaps declined, but remained high in President Trump’s second year.

In Yemen, the Trump administration carried out an unprecedented escalation. The U.S. Central Command (CENTCOM) stated that it conducted 131 strikes in Yemen in 2017, as well as multiple ground raids.⁸² That is more than three times the 43 U.S. counterterrorism operations reportedly carried out in 2016, according to New America’s tracking. It is also more than twice the 56 strikes carried out in 2012 at the peak of the campaign, according to New America’s data.

New America, which tracks only individually reported strikes, identified 48 counterterrorism operations in 2017. CENTCOM has repeatedly failed to respond to requests for individualized date and location information on the 131 strikes it reported having carried out in 2017.In 2018, the second year of the Trump administration, the pace of strikes in Yemen has lessened but remains high. As of the end of August, there have been 41 strikes in Yemen in 2018, according to New America’s data. This is far lower than the 131 CENTCOM reported for 2017 but still higher than all but three years of the campaign in Yemen, according to New America’s research.CENTCOM does not acknowledge all of these strikes. In emails to New America, CENTCOM confirmed a total of 34 strikes in Yemen through the end of August 2018 (one in August, two in July, two in June, two in May, four in April, seven in March, six in February, and ten in January).⁸³ It is unclear whether this discrepancy is due to misreporting of strikes by news media or the United States conducting strikes through means other than CENTCOM.

In Somalia, the Trump administration has also escalated strikes. In 2017, the United States carried out 34 strikes in Somalia, according to New America’s research — more than twice the prior peak of 13 strikes in 2016. In 2018, the pace of strikes appears to be slightly lower with 21 reported through the end of August, but still more than any prior year other than 2017.Despite the substantial changes and escalation under Trump, there should be caution in attributing the escalating strikes to him alone. The conduct of America’s counterterrorism wars is driven in large part by conditions on the ground.Notably in Pakistan, the Trump administration has not substantially escalated the drone war.⁸⁴ The administration did end a nine-month pause in reported drone strikes when it conducted a strike in South Waziristan on March 2, 2017. However, the number of strikes has remained low.

The Trump administration conducted only eight strikes in Pakistan in 2017, according to New America’s research. That is fewer strikes than the Obama administration conducted in any year except 2016, when the nine-month pause began. It is also far lower (more than 15 times lower) than the 122 strikes the Obama administration conducted at the peak of the drone campaign in Pakistan in 2010. In 2018, the United States has conducted five drone strikes in Pakistan as of the end of August, according to New America’s research.There are many possible reasons for the decline in strikes in Pakistan. One likely key factor is that the United States now has far fewer troops in Afghanistan than it did in 2010 and thus less need to carry out strikes to protect its forces. Another likely key factor is that Pakistan carried out a major military operation in its northwest tribal regions in 2015 that drove many militants into Afghanistan and killed others, reducing the number of militant targets in Pakistan. Both of these factors illustrate the importance of matters beyond the Trump administration’s policy changes in the conduct of the drone war.

In Libya, the Obama administration carried out a major escalation of airstrikes in 2016, conducting 510 strikes, up from only two in 2015, according to research by New America and Airwars.⁸⁵ This major escalation was the result of a decision in the second half of 2016 to authorize strikes against ISIS in and around Sirte, Libya.⁸⁶ Counter to the thesis that the Trump administration’s particular policies and attitude toward counterterrorism strikes — rather than the context on the ground — have driven an escalation, the number of strikes in Libya fell in 2017 to 17 and again in 2018 to only five strikes as of the end of August, according to New America and Airwars research.⁸⁷Furthermore, even where strikes have escalated, the particular role of Trump can be overstated. The Trump administration’s escalation in Yemen was preceded by an increase in reported strikes from 24 in 2015 to 43 in 2016, the last year of the Obama administration. Similarly in 2016, the Obama administration conducted 13 strikes in Somalia, more than twice as many as in 2015 or in any prior year, according to New America’s research.

The jihadist terrorist threat to the United States is relatively limited. The threat posed by ISIS is receding, and the number of terrorism-related cases in the United States has declined substantially since its peak in 2015, though the nature and level of the threat is unlikely to change in a fundamental manner.

The most likely threat to the United States comes from terrorists inspired by ISIS or in contact with its virtual recruitment networks, as opposed to ISIS-directed attacks of the sort seen in Paris in 2015 and Brussels in 2016. The most typical threat to the United States remains homegrown rather than from infiltrating foreign nationals. The travel ban is thus not an effective response to this threat. Finally, the United States faces a continued threat from non-jihadist terrorists, most notably those motivated by far-right ideologies.

The threat to the United States from jihadist terrorism remains relatively limited. New America’s “Terrorism in America After 9/11” project tracks the 449 cases of individuals who have been “charged” with jihadist terrorism-related activity in the United States since September 11, 2001.⁸⁸

In the 17 years since the 9/11 attacks, individuals motivated by jihadist ideology have killed 104 people inside the United States. Every one of those deaths is a tragedy, but they are not national catastrophes as 9/11 was. The death toll from jihadist terrorism over the past 17 years is far lower than what even the most optimistic of analysts projected in the immediate aftermath of the 9/11 attacks. Al-Qaeda and its breakaway faction, ISIS, have failed to direct a successful attack in the United States since the 9/11 attacks. Indeed, no foreign terrorist organization has carried out a successful attack in the United States since 9/11, and none of the perpetrators of the 13 lethal jihadist attacks in the United States since 9/11 received training from a foreign terrorist group.

The rise of ISIS caused many to fear that the threat had fundamentally changed. Yet four years after the declaration of the caliphate, ISIS has not managed to direct an attack inside the United States, and its territorial losses make it increasingly unlikely that it will do so in the future.

ISIS did manage to inspire an unprecedented number of Americans to conduct attacks and otherwise engage in jihadist activity. In 2015, 80 people were charged with jihadist terrorism activity, the highest number in the post-9/11 era. More than three-quarters of all deaths caused by jihadists in the United States since the 9/11 attacks occurred in 2014 or later, the period when ISIS came to prominence, despite those years accounting for less than a third of the post-9/11 era. More than half of the deadly attacks since 9/11 were ISIS-inspired in some way.

The threat posed by ISIS is receding, and the number of terrorism-related cases in the United States has declined substantially.

However, ISIS’ ability to inspire such activity is declining with the demise of its territorial holdings in Iraq and Syria and the resultant stanching of the “foreign fighter” flow to the region. The number of cases of individuals being charged with terrorism-related crimes has decreased since the peak of 80 cases in 2015. There has been a particularly low number of charges brought this year, with only eight new cases as of the end of August.

Policymakers and analysts should not expect the threat to the United States to fundamentally change as a result of the collapse of ISIS’ holdings in Iraq and Syria. Because the ISIS threat to the United States was homegrown, inspired and relatively limited even at the peak of ISIS’ strength, rather than being directed from Syria, the impact of ISIS’ territorial collapse on the threat is limited.⁸⁹ While the number of cases has declined since 2015, ISIS-inspired attacks have continued, as demonstrated by Sayfullo Saipov’s truck ramming attack that killed eight people in Manhattan in October 2017, the same month that ISIS lost control of its capital in Raqqa.

In addition, policymakers should be wary of reading too much into the number of prosecutions. There may be cases that are not yet public but were charged in 2018, and the number of prosecutions can reflect prosecutorial decisions regarding how aggressive to be. That said, the low number of cases is notable.

The limited threat to the United States is in large part the result of the enormous investment the country has made in strengthening its defenses against terrorism in the post-9/11 era. According to a study group created by the Stimson Center, one of whose members was Luke Hartig, a New America International Security program fellow and former senior director for counterterrorism at the National Security Council, the United States spent $2.8 trillion on counterterrorism efforts from 2002 to 2017, constituting almost 15 percent of discretionary spending during that time frame.⁹⁰

That effort has made the United States a hard target.⁹¹ On 9/11, there were 16 people on the U.S. “No Fly” list.⁹² In 2016, there were 81,000 people on the list.⁹³ In 2001, there were 35 Joint Terrorism Task Force “fusion centers,” where multiple law enforcement agencies worked together to chase down leads and build terrorism cases.⁹⁴ Seventeen years later, there are more than 100.⁹⁵ Before 9/11, there was no Department of Homeland Security, National Counterterrorism Center or Transportation Security Administration.

In addition, today the public is far more aware of the threat posed by jihadist terrorists. In December 2001, it was passengers on board an American Airlines jet that disabled the “shoe bomber,” Richard Reid.⁹⁶ Eight years later, it was again passengers who tackled the “underwear bomber,” Umar Farouk Abdulmutallab, on Northwest Flight 253 as it flew over Detroit. The following year, it was a street vendor who spotted a suspicious SUV parked in Times Square that contained a bomb planted there by Pakistani Taliban recruit Faisal Shahzad.⁹⁷ Suspicious members of the public have provided tips that led to the initiation of investigations in 7 percent of the 407 terrorism cases since 9/11 that were prevented or detected before the perpetrator could carry out a plot.

Policymakers and analysts should not expect the threat to the United States to fundamentally change as a result of the collapse of ISIS’ holdings in Iraq and Syria.

In addition to the general public’s awareness, family members of accused terrorists and members of their local communities have also stepped up to report suspicious activity. In 14 percent of jihadist terrorism cases since 9/11 that were prevented or detected prior to an attack, community or family members provided a tip that initiated the investigation — the second most important method of detecting terrorism suspects, surpassed only by informants, who initiated 22 percent of cases.

Among those detected thanks to tips from community and family members was Moner Abu Salha, a Floridian who traveled and fought with the Nusra Front in Syria before returning to the United States undetected. When he tried to recruit friends to join him in Syria, where he eventually died conducting a suicide attack against Syrian troops in 2014, one of his friends reported him to the FBI.⁹⁸ Similarly, it was a 911 call from the parents of North Carolinian Justin Sullivan in June 2015 that put him on the government’s radar.⁹⁹ Had it not been for that tip, Sullivan, who had already committed a murder and who was in contact with Junaid Hussain, an ISIS virtual recruiter, might have succeeded in his plot to conduct a lethal attack.¹⁰⁰

Adding to these defenses and law enforcement techniques are the U.S. campaigns overseas. In 2017, the United States allocated more than $73 billion to intelligence activities.¹⁰¹ Before 9/11, the budget was about one third of that — $27 billion.¹⁰² The U.S. drone wars in Pakistan, Yemen and elsewhere have decimated the leadership of jihadist groups.¹⁰³ In June 2018, an American drone strike in Afghanistan killed Mullah Fazlullah, the leader of the Pakistani Taliban.¹⁰⁴ In April 2018, the United States killed the ISIS Afghanistan branch’s leader for northern Afghanistan.¹⁰⁵ In July 2017, the United States killed Abu Sayed, the leader of ISIS’ branch in Afghanistan; he was the third leader of the affiliate killed in an American strike in a year.¹⁰⁶ In May 2016, the United States killed the leader of the Taliban, Mullah Akhtar Mohammad Mansour, in a drone strike in Pakistan.¹⁰⁷ In 2015, a U.S. drone strike killed Nasir al-Wuhayshi, then al-Qaeda’s second in command and the leader of Al-Qaeda in the Arabian Peninsula.¹⁰⁸

By the start of the Trump administration, the threat inside the United States was overwhelmingly lone-actor, ISIS-inspired attacks such as the one in Orlando in June 2016. This threat has stressed law enforcement, given the diversity of the perpetrators and the lack of organization needed to conduct such attacks. However, it is a far cry from the type of attack that al-Qaeda carried out on 9/11.

Law enforcement and intelligence services will of course still need to combat and monitor the threat to the homeland from foreign terrorist organizations. Plots such as the 2009 underwear bomb attempt; the 2009 case in which three Americans trained with al-Qaeda and returned with a plan to bomb the New York City subway; and the 2010 failed Times Square bombing by Faisal Shahzad, who trained with the Pakistani Taliban, are sufficient reminders of this fact.

Since 2014, the year ISIS burst onto the global scene after seizing Mosul and declaring the caliphate, there have been eight deadly jihadist attacks in the United States. Eighty-three people were killed, accounting for more than three-quarters of all deaths caused by jihadists in the United States since the 9/11 attacks. Seven of the eight were ISIS-inspired attacks, the exception being Muhammad Youssef Abdulazeez’s 2015 attacks at a recruiting station and a U.S. Navy Reserve center in Chattanooga, Tennessee, inspired by jihadist ideology in general.

• In March 2018, Corey Johnson, a 17-year-old white convert, stabbed three people during a sleepover in Palm Beach Gardens, Florida — a 13-year-old boy, another teenager and that teen’s mother — killing the 13-year-old.¹⁰⁹ According to police, Johnson had converted to Islam, watched jihadist videos online and admitted to committing the stabbings due to his religious beliefs.
• In October 2017, Sayfullo Saipov, a 29-year-old Uzbek permanent resident of the United States, killed eight people when he drove a truck into the Hudson River Park’s bike path in New York City.¹¹⁰ Saipov left a note saying he conducted the attack for ISIS.
• In January 2017, Joshua Cummings, a 37-year-old white convert to Islam from Texas, shot and killed a transit guard in Denver, Colorado. In the aftermath of the attack, Cummings pledged allegiance to ISIS.¹¹¹ ISIS did not claim Cummings’ attack.
• In June 2016, Omar Mateen killed 49 people in a shooting at the Pulse nightclub in Orlando, Florida. Mateen pledged allegiance to ISIS on social media the day of the attack.¹¹² Unlike the case of Cummings, ISIS eagerly claimed Mateen’s attack.
• In December 2015, Syed Rizwan Farook and Tashfeen Malik killed 14 people in an attack in San Bernardino, California. The attackers pledged allegiance to ISIS via Facebook.¹¹³ ISIS claimed the attack, though the Arabic version of the claim described the attackers only as supporters of ISIS.¹¹⁴ Shortly after the attack, then-FBI Director James Comey said the FBI had not found any evidence of contact between Farook and Malik and foreign terrorists.¹¹⁵
• In July 2015, Mohammad Youssef Abdulazeez fatally shot five people at military facilities in Chattanooga, Tennessee. In December 2015, Comey stated, “There is no doubt that the Chattanooga killer was inspired, motivated by foreign terrorist organization propaganda,” but he also said it was difficult to determine which group specifically inspired him.¹¹⁶ Abdulazeez did not pledge allegiance to ISIS, and ISIS did not claim the attack.
• In September 2014, Alton Nolen beheaded a coworker of his at the Vaughn Foods processing center in Moore, Oklahoma. Nolen had an ISIS flag in his car and his social media activity suggested he was influenced by jihadist ideology.¹¹⁷ ISIS had no direct involvement in the attack.
• From April to June 2014, Ali Muhammad Brown fatally shot four people in a killing spree across Washington state and New Jersey, writing in his journal that he supported ISIS and telling police that he committed the killings in retaliation for American foreign policy.¹¹⁸ Brown did not receive operational direction from ISIS.

A number of these attackers had personal troubles. This should warn against explaining their acts simply as motivated by militant Islamist ideology:

• Corey Johnson had a long history of fascination with extremist violence of multiple stripes — not just jihadism — including white supremacy and dictators like Stalin and Hitler.¹¹⁹ He also had a history of behavioral issues and according to one report he stalked a fellow student while in middle school.¹²⁰
• Joshua Cummings had clashed with multiple people in his community. His local newspaper in Texas, the Pampa News, had stopped publishing his stories on martial arts — Cummings had taught martial arts classes at a studio in Pampa — in 2015 due to his obsessions and conspiracy theorizing.¹²¹
• Omar Mateen had a long history of stalled career goals, disruptive behavior and domestic violence.¹²²
• Mohammad Abdulazeez suffered from depression.¹²³
• There are significant questions regarding Alton Nolen’s mental health. Though he was ruled competent to stand trial, Nolen’s defense presented evidence that he suffers from mental health issues, and the psychologist cited by the prosecution acknowledged he had symptoms of mental illness but argued there was not enough for a diagnosis.¹²⁴ In addition, Nolen’s attack was triggered by his suspension from work, albeit seemingly for a complaint regarding his racial politics.¹²⁵ He reportedly told police he was motivated by what he viewed as discrimination in the workplace.¹²⁶ Nolen also had a criminal history involving drug charges and assault and battery of a police officer, for which he served two years in prison.¹²⁷
• Ali Muhammad Brown was in the midst of what the judge in his case called a “downward spiral of criminality,” having previously been convicted of bank fraud, assault and communication with a minor for immoral purposes.¹²⁸

There have been 12 nonlethal terrorist attacks in the United States since 2014 by individuals motivated by jihadist ideology, mostly by ISIS.

• On January 14, 2018, Tnuza Hassan, a 19-year-old U.S.-born citizen, set a series of fires at St. Catherine University in Minnesota, where she had been a student, as retaliation for U.S. foreign policy.¹²⁹ No one was hurt in the incident, and she was later charged with attempting to provide material support to terrorists with relation to attempts to join jihadists abroad, arson and false statements.¹³⁰
• On December 11, 2017, Akayed Ullah, a 27-year-old legal permanent resident from Bangladesh, detonated a pipe bomb near New York’s Port Authority bus terminal, injuring five people.¹³¹ Ullah pledged allegiance to ISIS, saying he conducted the attack for them.
• On November 12, 2017, Mahad Abdirahman, a 20-year-old naturalized citizen from Somalia who had been ruled to be suffering from schizophrenia and spent much of 2017 before his attack in a mental institution, stabbed and injured two people at the Mall of America in Bloomington, Minnesota.¹³² Abdirahman said during court proceedings that he conducted the attack for ISIS.¹³³
• On June 21, 2017, Amor Ftouhi, a 49-year-old dual Canadian-Tunisian citizen, stabbed and injured a security guard at the airport in Flint, Michigan, yelling “Allahu Akbar!” and referencing U.S. actions in Syria.¹³⁴
• In November 2016, Abdul Razak Ali Artan, an 18-year-old permanent resident who had come to the United States as a refugee from Somalia after living in Pakistan, injured 11 people after ramming his vehicle into and proceeding to stab people with a knife at Ohio State University.¹³⁵ ISIS claimed the attack, and Artan had made a Facebook posting citing Anwar al-Awlaki prior to the attack.¹³⁶
• In September 2016, Dahir Adan, a 20-year-old Somali-American naturalized citizen, injured 10 people when he went on a stabbing rampage at a mall in Minnesota. ISIS claimed the attack, but investigators have found no direct link to the group.¹³⁷
• Also in September 2016, Ahmad Khan Rahami, a 28-year-old naturalized citizen whose journal mentioned both ISIS and al-Qaeda leaders, detonated bombs in Manhattan and at the Jersey Shore, injuring 31 people.¹³⁸
• In August 2016, Wasil Farooqui, a 20-year-old U.S.-born citizen who according to police said he was hearing voices, attacked people with a knife in Roanoke, Virginia.¹³⁹ Farooqui had reportedly attempted to travel to fight in Syria in the past.¹⁴⁰
• In January 2016, Edward Archer, a 30-year-old African-American man, shot and injured a police officer in Philadelphia. Archer claimed to be loyal to ISIS.¹⁴¹
• In November 2015, Faisal Mohammad, 18, a student at the University of California, Merced and U.S.-born citizen, stabbed and injured four people on the campus.¹⁴² According to the FBI, he had visited pro-ISIS websites, read its propaganda and had a printout of the ISIS flag in his backpack.¹⁴³
• In May 2015, two U.S.-born citizens, Elton Simpson, 30, and Nadir Soofi, 34, opened fire on an “art contest” in Garland, Texas, organized by the American Freedom Defense Initiative that involved drawing cartoons of the Prophet Muhammad. Simpson had exchanged tweets with Mujahid Miski and Junaid Hussain, two well-known ISIS virtual recruiters who were based in Somalia and Syria, respectively, in the run-up to the attack.¹⁴⁴ This was the only ISIS-enabled — as opposed to ISIS-inspired — attack in the United States injuring one person before the gunmen were killed by police.
• In October 2014, Zale Thompson, a 32-year-old U.S.-born citizen, attacked four police officers in Queens, New York, with a hatchet. According to New York City police, he was inspired by terrorist propaganda including that of ISIS.¹⁴⁵

As with the deadly attackers, some of the nonlethal attackers had prior personal issues, histories of violence or mixed ideological influences that raise questions as to the role of ISIS ideology as primary driver of the violence. For example, though Zale Thompson was reportedly inspired in part by ISIS propaganda, an FBI threat assessment on Black Identity Extremism claimed he had tattoos and pocket litter tied to black separatist groups, and a 2017 National Counterterrorism Center report, “Sunni Violent Extremist Attacks in the United States since 9/11,” stated there was no intelligence community consensus on his motive.¹⁴⁶ Thompson also had multiple run-ins with the law over domestic violence accusations before his attack.¹⁴⁷

Similarly, four of the 13 attackers had reported mental health issues. At the more severe end of the spectrum, Mahad Abdirahman was ruled to have schizophrenia and had spent most of the year of his attack in a mental institution.¹⁴⁸ Wasil Farooqui reportedly was hearing voices at the time of his attack, was diagnosed with schizoaffective disorder, and had previously been institutionalized.¹⁴⁹ Edward Archer’s mother claimed he had been suffering from mental health issues and had been hearing voices.¹⁵⁰ At the seemingly less severe end of the spectrum, Zale Thompson reportedly struggled with depression and drug use.¹⁵¹

With the exception of the attack on the “art contest” in Garland, Texas, where the attackers were in contact over the internet with ISIS operatives abroad, these attacks were inspired attacks in which ISIS and/or other foreign terrorist groups did not play an operational role or provide direction. While the nonlethal attackers used a diverse variety of weapons, eight of the 13 attacks utilized bladed weapons, vehicular ramming, or arson in the case of Tnuza Hassan — methods that may explain their lack of lethality compared to the firearms used by five of the eight lethal terrorist attackers since 2014.

These attacks were inspired attacks in which ISIS and/or other foreign terrorist groups did not play an operational role or provide direction.

While the incident in Garland has been the only ISIS-enabled attack in the United States, there have been several foiled plots in which ISIS’ virtual recruiters sought to encourage and aid attacks.¹⁵² These include a foiled plan by three men in Boston in June 2015 to attack Pamela Geller, the organizer of the Prophet Muhammad cartoon contest in Garland.

One case in particular that illustrates the danger of ISIS-enabled plots is that of Justin Sullivan. Before his arrest in June 2015, Sullivan plotted with Syria-based ISIS recruiter Junaid Hussain to conduct an attack.¹⁵³ He agreed at Hussain’s behest to make a video of the attack that could be used by ISIS in its propaganda.¹⁵⁴ The danger that Sullivan posed is emphasized by his conviction for a murder, in which he shot and killed his neighbor.¹⁵⁵

The conclusion that the threat to the United States is ISIS-inspired and ISIS-enabled, but not ISIS-directed, mirrors the statements of a variety of government officials. In February 2018, Director of National Intelligence Dan Coats testified, “US-based homegrown violent extremists (HVEs) will remain the most prevalent Sunni violent extremist threat in the United States.”¹⁵⁶ Coats testified similarly in 2017.¹⁵⁷ In December 2017, FBI Director Christopher Wray testified, “Currently, the FBI views ISIS and homegrown violent extremists as the main terrorism threats to the United States.”¹⁵⁸ In May 2017, Nicholas Rasmussen, then-director of the National Counterterrorism Center, stated: “We certainly know that al-Qa‘ida and ISIS continue to aspire to carry out significant attacks on U.S. soil, but they are challenged to do so.”¹⁵⁹

On January 27, 2017, a week after being sworn in as president, Donald Trump signed an executive order instituting a travel ban on foreign nationals from seven majority-Muslim countries: Iran, Iraq, Syria, Sudan, Libya, Yemen and Somalia. The order also halted U.S. entry for Syrian refugees and capped the total number of refugees allowed entry in 2017 at 50,000. As a result of court challenges and international outcry, the ban was narrowed to not apply to those with close family members in the United States. Iraq was also dropped from the list of countries. The revision kept the 50,000-refugee cap in place and put a 120-day freeze on entry of any refugee starting June 29, 2017. Further revisions added Chad to the list and more limited restrictions on travelers from Venezuela and North Korea, and dropped Sudan and eventually Chad. The Supreme Court upheld the third version of the travel ban in a 5-4 decision in June 2018.

The administration justified its travel ban by arguing, “Numerous foreign-born individuals have been convicted or implicated in terrorism-related crimes since September 11, 2001.”¹⁶⁰ Yet, the travel ban would not have prevented a single death from jihadist terrorists since 9/11. Nor would it have prevented the 9/11 attacks, which were perpetrated by 15 Saudis, two Emiratis, an Egyptian and a Lebanese citizen — all from countries that are not on the travel ban list.

The threat to the United States is largely homegrown. Eighty-four percent of the 449 individuals tracked by New America and accused of jihadist terrorism-related crimes in the United States since 9/11 were either U.S. citizens or U.S. legal residents.¹⁶¹ Just under half of them, 223, were born American citizens. Around a three in ten were converts.

Syrian refugees settled in the United States have not posed a threat, either. No lethal act of jihadist terrorism since 9/11 has been carried out by a Syrian refugee. An ISIS terrorist with any sense is quite unlikely to try to infiltrate the United States as a Syrian refugee. Anne Richard, a senior U.S. State Department official, testified at a Senate Homeland Security Committee hearing in November 2015 that any Syrian refugee trying to get into the United States is scrutinized by officials from the National Counterterrorism Center, FBI, Department of Homeland Security, State Department and Pentagon. Further, Leon Rodriguez, then the director of U.S. Citizenship and Immigration Services, who also testified at the November 2015 hearing, said that of the millions of people who try to get into the United States each year, “Refugees get the most scrutiny and Syrian refugees get the most scrutiny of all.”¹⁶² This scrutiny can take up to two years.

Eighty-four percent of the 449 individuals tracked by New America and accused of jihadist terrorism-related crimes in the United States since 9/11 were either U.S. citizens or U.S. legal residents.

Every lethal attacker since 9/11 was either a citizen or permanent resident of the United States at the time of the attack, and none came from a country covered by the travel ban. Nine, more than half, of the 15 deadly attackers were born in the United States.¹⁶³

*On March 6, 2017 the Trump administration issued a new executive order, which did not include Iraq in the list of visa restricted countries. On September 24, 2017, the travel ban was revised again to drop Sudan, and add travel restrictions regarding Venezuela and North Korea (not displayed on this map), as well as Chad.

Among the individuals who conducted potentially lethal attacks inside the United States that were foiled or otherwise failed to kill anyone, there are only four cases that the travel ban could have applied to. None provides a convincing argument for the travel ban. In one case, Mohammed Reza Taheri-Azar, a naturalized citizen from Iran, drove a car into a group of students at the University of North Carolina in 2006, injuring nine people.¹⁶⁴ However, Taheri-Azar came to the United States at the age of 2 with his parents, and according to his older sister spoke no Arabic and only rudimentary Farsi.¹⁶⁵ He conducted his attack about two decades after arriving in the United States. His radicalization did not occur in Iran but in the United States.

Similarly, Dahir Adan, who committed the stabbing at a mall in Minnesota in 2016, was a naturalized citizen from Somalia, though he was born in Kenya.¹⁶⁶ Like Taheri-Azar, Adan came to the United States as a young child and his radicalization occurred in the United States, not abroad.¹⁶⁷

Abdul Razak Ali Artan was a legal permanent resident who came to the United States as a refugee from Somalia in 2014, having left Somalia for Pakistan in 2007. In 2016, at age 18, he rammed a car into his fellow students on the campus of Ohio State University and proceeded to attack them with a knife, injuring 11 people. However, it is not clear that the attack provides support for the travel ban. Artan left Somalia as a pre-teen, and if he was radicalized abroad, it most likely occurred in Pakistan, which is not included in the travel ban. In a Facebook posting before his attack, Artan cited Anwar al-Awlaki, the Yemeni-American cleric born in the United States, whose writings have helped radicalize a wide range of extremists in the United States.

Finally, there’s Mahad Abdirahman, a 20-year-old naturalized citizen born in Somalia, who stabbed and injured two men at the Mall of America on November 12, 2017. During his trial, Abdirahman stated he was inspired by ISIS. However, Abdirahman’s case is far from clear evidence for the travel ban. He had previously been hospitalized for mental illness and was prescribed medication that he had stopped taking. He also faced an earlier assault charge, having stabbed a psychiatrist with a pen.

The Department of Homeland Security’s own analysis from February 2017 undercuts the justification for the travel ban. The DHS report, which was leaked, assessed that “country of citizenship is unlikely to be a reliable indicator of potential terrorist activity” and found that half of the 82 extremists it examined were native-born American citizens. DHS determined that those who were born abroad came from 26 different countries, with no single country accounting for more than 13.5 percent of the total, and that three of the travel ban countries (Iran, Sudan and Yemen) had only one extremist in the assessment who was born there, while there were no individuals from Syria.¹⁶⁸

The DHS report assessed that “country of citizenship is unlikely to be a reliable indicator of potential terrorist activity” and found that half of the 82 extremists it examined were native-born American citizens.

Another leaked DHS report, from March 2017, which examined the origins of 88 foreign-born extremists, assessed that “most foreign-born US-based violent extremists likely radicalized several years after their entry to the United States, limiting the ability of screening and vetting officials to prevent their entry because of national security concerns.”¹⁶⁹ The report found that about half of foreign-born extremists were younger than 16 when they entered the country and the majority had lived in the United States for 10 years before their indictment or death.¹⁷⁰

A report authored by the Cato Institute’s David Bier found only 13 post-9/11 vetting failures in which an individual entered the United States and committed a terrorism-related crime after 9/11.¹⁷¹ The report also found that the rate of vetting failure was 99.5 percent lower following 9/11 and the resultant reforms to immigration security, despite using a broad definition of vetting failure.

Only one vetting failure identified by the Cato study, which covered the period from 2002 through 2016, involved a deadly attack — a rate of one for every 379 million visa or status approvals.¹⁷² That failure was the entry of Tashfeen Malik, who conducted her attack alongside her husband, a natural-born U.S. citizen who had already acquired the weapons used in the attack and plotted violence before her entry. In addition, Malik was born in Pakistan and would not have been covered by the travel ban.

This does not mean the system is perfect. In August 2018, the United States arrested Omar Ameen, a 45-year-old Iraqi who had come to the United States as a refugee, in order to extradite him to Iraq where he faced charges for a June 22, 2014, murder of a police officer in support of ISIS. According to court records, Ameen had been a member of ISIS and its precursor groups since 2004 and faced two prior warrants for arrest before he entered the United States.¹⁷³ His entry represents a relatively major failure of the system that requires review. However, the court documents do not refer to any terrorist plotting within the United States, and the vetting failure in Ameen’s case is a rarity among the terrorism cases involving U.S. persons.

The Trump administration has marshalled its own politicized and highly misleading data to justify the travel ban and its immigration and border security-centric counterterrorism effort. A joint report by the Justice and Homeland Security departments in January 2018 asserted that “Three Out of Four Individuals Convicted of International Terrorism and Terrorism-Related Offenses were Foreign-Born.”¹⁷⁴

The DOJ-DHS report is highly misleading.¹⁷⁵ First, even taking the report at face value, it suggests that the threat is largely homegrown, with a majority of cases being citizens and a quarter being natural-born citizens. Second, the report includes among the international terrorism cases it examines numerous examples of individuals extradited to the United States, who are simply not immigrants. Though the exact data underlying the report is not available, by some accounts it may include as many as 100 cases of individuals who were extradited.¹⁷⁶ In addition, by using international terrorism cases, the report excludes domestic terrorism cases — particularly those motivated by far-right and similar ideologies — yet this cannot be justified by focusing on the jihadist threat, as the report includes cases involving the FARC and other non-jihadist groups. Third, the report assumes that naturalized citizens are meaningfully distinct from natural-born citizens and represent a border security issue, without providing evidence. In fact, as the aforementioned leaked DHS reports show, this is at odds with DHS’ own findings in other reviews of the data. White House adviser Stephen Miller sought to explicitly include language emphasizing the threat from children of foreign born citizens in the report, a goal that DHS Secretary Kirstjen Nielsen reportedly objected to because it was unsubstantiated.¹⁷⁷ Fourth, the report looks only at federal convictions for terrorism-related crimes and thus misses multiple important cases of U.S.-born citizens including Omar Mateen, who died conducting the Orlando attack; Carlos Bledsoe, who was charged with murder in state court for his 2009 attack on a military recruiting station in Arkansas; and Nidal Hasan, an Army major and psychiatrist who was charged in military court for his attack on Fort Hood in Texas.

Today’s extremists in the United States radicalize online, and the internet knows no visa requirements. Just under half of the jihadists charged in the United States since 9/11 either maintained a social media account where they posted jihadist material or interacted with extremists via encrypted communications; in recent years, an active online presence has been almost universal among American jihadists.¹⁷⁸

The attack in Garland, Texas, described in detail above, is a case in point. Not only were the perpetrators both native-born American citizens who would not have been stopped by the travel ban, but their interlocutors from ISIS did not set foot in the United States, instead encouraging the plot through online communication. The travel ban does nothing to respond to the most likely threat today: ISIS-inspired and ISIS-enabled homegrown attacks.

The threat posed by American “foreign fighters” returning to the United States is quite limited. To date, no one who fought for ISIS or other extremist groups in Iraq or Syria has committed an act of terrorism in the United States after returning, according to a review of cases conducted by New America.

Of the few Americans who have fought with militant groups in Syria and returned, only one, Abdirahman Sheik Mohamud, conspired to carry out an attack. Mohamud, a Somali-American, traveled to Syria to join the Nusra Front in April 2014, only three months after he became a naturalized citizen. He returned to the United States that June and shortly thereafter communicated with an unnamed individual about his desire to travel to a military base in Texas and kill three or four U.S. soldiers.¹⁷⁹ Mohamud was arrested in February 2015 — before attempting to carry out this plot — and pleaded guilty to material support charges in June 2017.

Today’s extremists in the United States radicalize online, and the internet knows no visa requirements

This conclusion is shared by a February 2018 report from George Washington University’s Program on Extremism, which stated, “Only one of the 12 returnees identified in this study returned with the intent to carry out an attack on behalf of a jihadist group in Syria.”¹⁸⁰

The threat from returning foreign fighters should of course be an area of focus for U.S. Customs and Border Protection officials and those in the intelligence and law enforcement communities tasked with protecting the homeland.

The terrorist threat in the United States does not emanate only from individuals motivated by jihadist ideology. The broader challenge is from individuals who plan and commit political violence motivated by a range of ideologies, including far-right, black nationalist and left-wing causes, as well as idiosyncratic notions.

New America has found that since 9/11, individuals motivated by far-right ideology and/or belonging to organizations with such motivations have killed 73 people in the United States, while individuals motivated by black nationalist or separatist ideology have killed eight people.¹⁸¹

Since Donald Trump assumed the presidency, the United States has seen three deadly jihadist attacks: the shooting committed by Joshua Cummings in January 2017, the October 2017 vehicular ramming attack by Sayfullo Saipov, and the March 2018 stabbing by Corey Johnson. There have also been six lethal far-right-wing attacks. Four of these attacks have very clear political motivations, while two feature individuals with known extremist ties and beliefs who may have been motivated by personal issues rather than political ideology.

• On March 20, 2017, James Harris Jackson killed an African-American man with a sword in New York City after traveling from Baltimore for that purpose.¹⁸² Jackson was indicted on a rare state terrorism charge.¹⁸³ Jackson had liked alt-right YouTube videos and written an anti-black manifesto before his attack.¹⁸⁴
• On May 20, 2017, Sean Urbanski attacked and killed an African-American man who was visiting the University of Maryland.¹⁸⁵ Prosecutors initially did not assert that Urbanski had a racial or political motive, despite his belonging to a white supremacist Facebook group titled Alt Reich: Nation. However, in October 2017, prosecutors charged Urbanski with a hate crime in relation to the attack based on digital evidence from his computer.
• On May 26, 2017, Jeremy Christian, a 35-year-old active in violent right-wing “free speech” protests in Portland, Oregon, stabbed and killed two men who intervened when he was harassing two Muslim women on public transit.¹⁸⁶ During a court hearing, Christian declared, “Death to the enemies of America. Death to antifa [anti-fascists]. You call it terrorism. I call it patriotism. Die.”¹⁸⁷
• On Aug. 12, 2017, James Alex Fields Jr., a 20-year-old from Maumee, Ohio, rammed his car into a group of people in Charlottesville, Virginia, who were gathered to protest a white nationalist rally, killing a 32-year-old woman and injuring 19 others.
• In January 2018, prosecutors in Orange County, California, charged Samuel Woodward, a 20-year-old man, with stabbing and killing Blaze Bernstein, an openly gay and Jewish former classmate of his.¹⁸⁸ Woodward was a member of Atomwaffen Division, a neo-Nazi group, although investigators caution that his membership in the group may not have motivated the attack.¹⁸⁹ In August 2018, prosecutors added a hate crime enhancement to the accusations, alleging that Woodward killed Bernstein because he was gay.¹⁹⁰
• In July 2018, Ronald Lee Kidwell, a 47-year-old white man, was charged with the murder of MeShon Cooper, a 43-year-old black woman, whose body was discovered in a suburb of Kansas City, Kansas, after she was reported missing in early July. According to his family and neighbors, Kidwell held white supremacist views, bragged of being a member of the KKK, displayed the Confederate flag, and according to his daughter had a history of targeting black people for violence (he had previously pleaded guilty to assault in a 2011 case where the victim was also a black woman).¹⁹¹ According to court documents, Kidwell told law enforcement that he killed Cooper after an argument escalated, claiming she threatened to reveals his HIV-positive status.¹⁹² Law enforcement officials have not determined whether the murder was a hate crime and are still investigating.

In addition to the above attacks, on October 1, 2017, Stephen Paddock killed 58 people in a shooting at an outdoor music festival in Las Vegas. Paddock’s motive remains unclear, but witness statements released by law enforcement following a lawsuit include comments that suggest Paddock held conspiracy and anti-government views characteristic of the far right, and one witness claimed that Paddock told him, “Somebody has to wake up the American public and get them to arm themselves.”¹⁹³ The Las Vegas Police Department closed the investigation without determining a motive.¹⁹⁴

If the Las Vegas shooting was an anti-government terrorist attack, it would be the deadliest post-9/11 terrorist attack motivated by any ideology in the United States. It would also mean that far-right terrorist attacks have killed 131 people in the United States since 9/11, surpassing the death toll from attacks motivated by jihadist ideology.

The United States has also seen one deadly attack by an individual motivated by black nationalist ideology since Trump assumed office.¹⁹⁵ On April 18, 2017, Kori Ali Muhammad, a 39-year-old African-American man, was arrested and charged with killing three people in a shooting in Fresno, California.¹⁹⁶ Police said race was a factor in the murders and Muhammad’s social media presence included black nationalist posts. Muhammad’s father said his son believed he was part of a war between whites and blacks and that “a battle was about to take place.”¹⁹⁷

If the Las Vegas shooting was an anti-government terrorist attack, it would be the deadliest post-9/11 terrorist attack motivated by any ideology in the United States.

There have also been nonlethal acts of political violence. In August 2017, an explosive device was thrown into the Dar Al-Farooq Islamic Center in Bloomington, Minnesota, though no one was injured.¹⁹⁸ In March 2018, a federal grand jury indicted three men, who were part of an anti-government militia, in relation to the bombing as well as an attempted bombing of an Illinois abortion clinic.¹⁹⁹

The shooting attack by 66-year-old James T. Hodgkinson on Republican congressmen during a June 2017 baseball practice in Alexandria, Virginia, which did not kill anyone but injured multiple people including Representative Steve Scalise, the number three House Republican leader, suggests that political violence could again be emerging on the left.²⁰⁰

The United States has also seen serious foiled domestic terrorism plots. For example, in April 2018, three men were found guilty of plotting to bomb an apartment complex in Garden City, Kansas, that was home to the local Somali community.²⁰¹ Prosecutors said the men were part of a militia and had written a manifesto, while Attorney General Jeff Sessions called the guilty verdict “a significant victory against domestic terrorism and hate crimes.”²⁰² In May 2018, FBI Director Christopher Wray testified that the FBI had 1,000 open domestic terrorism investigations, a number similar to the 1,000 ISIS-related investigations the FBI says it has open.²⁰³ In July 2018, Miami Beach police arrested Walter Edward Stolper, a 72-year-old who had recently been served with eviction papers.²⁰⁴ According to police, Stolper planned to burn down his building, sought to target Jews specifically and had Nazi material in his apartment. Police stated, “Already in the building he had disposed of eight additional gas canisters down the trash chute from the 15th floor,” adding, “We were minutes away from a potentially deadly situation.”²⁰⁵

This violence takes place alongside public violence by individuals who are motivated not by a traditional, formal political ideology, but rather in response to the broader polarization and conspiracy theorizing affecting American political discourse, as well as by the amplifying role social media can play. In April 2018, Nasim Aghdam, a 29-year-old woman, shot and injured three people at YouTube’s headquarters in California before killing herself. According to police, Aghdam was upset at YouTube for policies she considered to be harming her effort to build an audience for her channel, where she expressed a range of views on a variety of issues.²⁰⁶ Similarly, in December 2016, a man fired a weapon inside a pizzeria in Washington, D.C., because he believed a conspiracy theory that the restaurant was in fact a secret front for a child sex ring run by senior Democratic Party officials.²⁰⁷ No one was wounded in that attack.

However, there is great potential for violence motivated by conspiracy thinking to turn into more clearly political violence. For example, Matthew Wright, 30, was charged with terrorism crimes for a standoff near the Hoover Dam on June 15, during which he blocked traffic with an armored car and an AR-15 rifle. He wrote letters to President Trump and other officials that included references to the QAnon conspiracy, which itself has a political framing that pits Trump as a hero fighting a conspiracy of the “deep state” and elites.²⁰⁸

This violence from political and nonpolitical motives other than jihadism emphasizes the need to address non-jihadist ideologies as well as warns against an overemphasis on ideology as a factor amid a larger range of public violence facing the United States today.

While the threat in the United States consists of attacks inspired — or in one case enabled — by ISIS, the threat in Europe is more severe, consisting of a mixture of attacks directed by ISIS and its affiliates as well as homegrown ISIS-enabled and ISIS-inspired attacks.

While the United States has experienced no attacks directed by foreign terrorist organizations since 9/11, there have been five ISIS-directed attacks in Europe since 2014:

• A May 2014 attack in which Mehdi Nemmouche killed four people in a shooting at the Jewish Museum of Belgium in Brussels. Nemmouche had been in contact with Abdelhamid Abaaoud, the mastermind of the November 2015 Paris attacks, and had guarded Western hostages held by ISIS core in Syria.²⁰⁹
• An August 2015 foiled attack on a train in Oignies, France, whose perpetrator, Ayoub El-Khazzani, traveled to Europe with Abaaoud.²¹⁰
• The November 2015 attacks in Paris, which killed 130 people, by terrorists trained in Syria and sent back to Europe by ISIS. The Paris attacks showed how a group of terrorists trained by a terrorist organization can mount operations more lethal than those carried out by homegrown terrorists without such training.
• The March 2016 bombing of the Brussels airport and metro, killing 32 people, by members of the same cell that conducted the attack in Paris.
• The May 2017 bombing of an Ariana Grande concert in Manchester, England, which killed 22 people, by Salman Abedi. Abedi had trained and been in close contact with ISIS operations planners in Libya.

The five ISIS-directed attacks in Europe since 2014 killed 188 people, almost two times the death toll of all deadly jihadist attacks in the United States since 9/11.²¹¹

Europe may have turned the corner regarding the immediate threat of ISIS-directed attacks. It has not seen an ISIS-directed attack since May 2017, and it has not seen an attack directed by ISIS core rather than an affiliate since March 2016. With the demise of ISIS’ territorial state in Syria and Iraq, attacks in Europe are increasingly likely to be ISIS-enabled or ISIS-inspired but not ISIS-directed. Where they are ISIS-directed, they are likely to be directed by ISIS’ affiliates rather than its core in Iraq and Syria.

In its 2018 report, Europol cited a “decrease in sophistication” in attack plots in the European Union in 2017.²¹² In addition, according to Europol, the number of arrests for jihadist terrorism in Europe stabilized and declined slightly to 705 in 2017 from 718 the previous year, after increasing every year from 2013 through 2016.²¹³ However, this decline is far less clear than that in the United States.

With the demise of ISIS’ territorial state in Syria and Iraq, attacks in Europe are increasingly likely to be ISIS-enabled or ISIS-inspired but not ISIS-directed.

Despite these promising signs, Europe faces a continued and substantial threat. While Europe may be turning the corner with regard to directed, sophisticated plots, Europol reported that the number of foiled, failed or successful jihadist attacks more than doubled from 13 in 2016 to 33 in 2017.²¹⁴

New America’s research, which tracks failed and successful attacks, suggests a similar trend. The number of attacks per year grew through 2017. This growth was driven by a steady increase in the number of attacks inspired by jihadist ideology in Europe but not known to have been directed or enabled by ISIS, even as attacks known to have closer ties to ISIS tapered off. As of the end of August, 2018 is not on pace to match the number of attacks in 2017. This may change, however, as the year ends.

Europe has experienced seven ISIS-enabled attacks since 2014,²¹⁵ compared to one in the United States. Twenty people have died in ISIS-enabled attacks in Europe, while no one other than the perpetrators has died in an ISIS-enabled attack in the United States. The last²¹⁶ ISIS-enabled attack in Europe occured in April 2017, when Rakhmat Akilov drove a truck into a crowd in Stockholm, Sweden, killing five people. Before the attack, Akilov shared images of his target and received a green light for the attack from his contacts via encrypted message.²¹⁷

Finally, there have been 46 attacks inspired by jihadist ideology in Europe that have not been directed or enabled by ISIS or other foreign terrorist organizations since 2014. These inspired attacks have killed 141 people in Europe since 2014, more than jihadist terrorists have killed in the United States during the 17 years since the 9/11 attacks.

Europe faces a more severe threat than the United States in large part due to four major factors: the large number of European foreign fighters, the larger and more developed nature of European jihadist networks, the marginalization of Muslims within Europe, and Europe’s geographic proximity to conflict zones.

Foreign Fighters

The first factor is the far larger number of foreign fighters who left for Syria and Iraq from Europe and the correspondingly large number of returnees. In its 2018 report, Europol estimated that about 5,000 Europeans had traveled to conflict areas in Syria and Iraq. By late 2017, Europol estimated, those in Syria numbered 2,500, with 1,500 having returned home and 1,000 having died.²¹⁸

These numbers are far greater than the number of Americans who have traveled to fight in Syria and Iraq. According to the FBI, 300 Americans have “traveled or attempted to travel to Syria and Iraq to participate in the conflict,” a number that appears to include those who fought with any group.²¹⁹ In addition, many of these Americans were arrested before setting foot in the conflict zone. Even with such caveats, the number of American “fighters” is more than 16 times smaller than the number of European fighters who actually traveled to Syria or Iraq.

The far larger number of European fighters is confirmed by ISIS’ own records. A set of 3,577 ISIS personnel records examined by New America contained 34 times as many fighters reporting residence in Western Europe than fighters reporting residence in the United States.

Correspondingly, the number of American returnees — likely in the tens — is also far lower than the 1,500 European returnees. In March 2015, then-Director of National Intelligence James Clapper stated that about 40 Americans had returned from Syria, though he suggested that some had gone for “humanitarian purposes.”²²⁰ Research by New America as well as the George Washington University Program on Extremism has identified fewer than 15 American returnees from Syria.²²¹

3,577 ISIS personnel records examined by New America contained 34 times as many fighters reporting residence in Western Europe than fighters reporting residence in the United States.

The large number of European foreign fighters increases the threat to Europe in several ways. First, such fighters were behind the far deadlier and more sophisticated set of directed attacks that hit Europe. However, the impact of returned European fighters is not limited to such directed attacks. Returnees can also act as organizers and facilitators, using their experience and knowledge to help build jihadist networks — whether to enable attacks by others or to enable terrorist travel, propaganda and fundraising activity.²²²

Beyond the threat of returnees from Syria conducting directed attacks or coordinating homegrown attacks by building networks, many of the returnees remain potential sources of inspired violence without direction from ISIS itself. The large radicalized population will remain a concern regardless of the state of ISIS control over operations.

The contours of the foreign fighter and returnee problem in Europe have shifted over time. For the time being, the flow of fighters to ISIS has been cut to at most a trickle. According to Europol’s 2018 report, “In 2017 there were considerably fewer EU-based FTFs [foreign terrorist fighters] travelling to conflict zones.”²²³ This continues a longer trend. Europol’s 2017 report assessed, “There is a decrease in the numbers of individuals travelling to the conflict zones in Syria/ Iraq to join the jihadist terrorist groups as foreign terrorist fighters.”²²⁴

In May 2017, then-National Counterterrorism Center Director Nicholas Rasmussen commented, “The good news is that we know that the rate of foreign fighters traveling has steadily declined since its peak in 2014.”²²⁵ Today, the flow to Syria and Iraq is essentially nonexistent.

That said, there are signs that there is still interest on the part of some militants and some level of sustained facilitation network activity for travel to conflict zones. For example, Europol notes that in June 2017, a Dutch man successfully reached ISIS in Syria (the first known case since November 2016).²²⁶ A search warrant in Minnesota alleges that an American attempted, but failed, to reach Syria via Europe in 2017 as well.²²⁷ Such cases do not provide reason to contest the finding that the number of travelers has declined precipitously. They do, however, warrant continued attention, particularly as the flow of fighters may increase again if another conflict becomes a popular field of jihad.

The flow of foreign fighter returnees back to Europe has also declined substantially. According to Europol’s 2018 report, in 2017 there was a “diminishing number of returnees” in part due to the difficulty of leaving ISIS territory as a result of military actions against ISIS.²²⁸ In July 2017 Rasmussen noted, “I look at the problem now as not so much as one of quantity but as one of quality,” emphasizing not the number of returnees but the skills that the small number of those who might return have obtained and how they might use them.²²⁹

There is a wild card with regard to European foreign fighter returnees, which is the unclear fate of the reportedly large number of Europeans currently imprisoned or detained in Syria and Iraq or otherwise remaining in the conflict zone. European countries have so far refused to take back hundreds of detained European fighters.²³⁰ This has resulted in some detained European fighters reportedly being released.²³¹ This produces the possibility that such fighters may return without being arrested at a later date, increasing the threat in Europe.

Jihadist Networks

The second factor compounding the threat in Europe is the existence there of stronger, more developed jihadist networks than exist in the United States. One reason ISIS was able to successfully conduct the November 2015 Paris attacks was that the attackers relied on a support network of at least 20 other people.²³² Similarly, Belgium tried 46 members of the radical group Sharia4Belgium who traveled to fight in Syria or helped others to do so.²³³ Those 46 are only a small portion of the larger Sharia4Belgium network.

As noted above, according to Europol, European states arrested 705 people in 2017 for jihadist terrorism, 718 people in 2016, and 687 in 2015.²³⁴ That is more jihadist terrorism-related arrests each year than have been made in the United States since 9/11.²³⁵ Over the three-year period from 2015 through 2017, European states arrested more people for jihadist terrorism-related crimes than the FBI reports having open investigations of ISIS-related crimes.²³⁶

Marginalization and Anti-Muslim Feeling

The third factor is that Europe faces more substantial challenges in successfully integrating its Muslim population than does the United States, and is thus likely to continue to struggle with a significant homegrown threat rooted in these challenges. In particular, the lack of opportunities and the identity challenges facing second-generation Muslim immigrants in Europe will likely continue to radicalize some for the foreseeable future.²³⁷

As a result of war, revolution, and poor economic and social conditions in the Middle East and North Africa, there has been an unprecedented wave of immigration from Muslim-majority countries into Europe in the past three years. Germany alone has taken in more than 1 million refugees and asylum seekers.²³⁸ European countries lack the ideological framework the United States has in the shape of the “American Dream,” which has helped to successfully absorb wave after wave of immigration, including Muslim Americans who are generally well integrated into American society.

The lack of opportunities and the identity challenges facing second-generation Muslim immigrants in Europe will likely continue to radicalize some for the foreseeable future.

There is no analogous French Dream or German Dream. The proportion of the French prison population that is Muslim is estimated to be around 60 percent, yet Muslims account for only about 8 percent of France’s total population.²³⁹ Muslim citizens in France are 2½ times less likely to be called for a job interview than similar Christian candidates, according to researchers at Stanford University.²⁴⁰ Many French Muslims live in grim banlieues, the suburbs of large French cities (similar to housing projects in the United States), where they find themselves largely divorced from mainstream French society. According to the Renseignements Généraux, a police agency that monitors militants in France, half the neighborhoods with a high Muslim population are isolated from French social and political life. The French term for these neighborhoods is equivalent to “sensitive urban zones,” where youth unemployment can be as high as 45 percent.²⁴¹ In Belgium there is a similar story: Twenty to 30 percent of the prison population is Muslim, yet Muslims make up only 6 percent of the overall population.²⁴²

It is not surprising that many of the perpetrators of attacks in Europe come from these economically marginalized communities or have spent time in French and Belgian prisons, which can function as universities of jihad. The members of the ISIS cell responsible for the November 2015 attacks in Paris that killed 130 and the March 2016 attacks in Brussels that killed 32 had bonded through criminal activities or in prison.²⁴³ Abdelhamid Abaaoud and Salah Abdeslam, the cell’s masterminds, were childhood friends who grew up in the impoverished Brussels neighborhood of Molenbeek. In 2010, the men were arrested and spent time in the same prison. Ibrahim Abdeslam, Salah’s brother, also spent time in prison with Abaaoud.²⁴⁴ He would go on to be one of the terrorists in the Paris attacks. Khalid and Ibrahim El Bakraoui, both suicide bombers in the Brussels attacks, had served lengthy prison sentences for armed robbery and assault on police.²⁴⁵

The marginalization of European Muslims and its role in jihadist radicalization is likely to be exacerbated by anti-Muslim and anti-immigrant feeling in Europe. Anti-immigrant, ultranationalist and anti-Muslim parties once played a marginal role in European politics. Although Emmanuel Macron defeated Marine Le Pen, the leader of France’s ultranationalist National Front (now called National Rally), in the French presidential election, Le Pen made it to the runoff with the second strongest showing in the first round race. Far-right parties also have expanded their power in Germany, the Czech Republic, Austria, the Netherlands, Italy and Poland, while left-wing parties have collapsed and center-right parties have moved rightward on immigration.²⁴⁶

In April 2018, anti-immigrant nationalist Viktor Orbán was reelected as prime minister in Hungary with overwhelming support.²⁴⁷ Orbán’s government proceeded to criminalize providing assistance to undocumented migrants.²⁴⁸ Before the election, Orbán called for a global anti-migrant alliance and stated, “Christianity is Europe’s last hope,” warning that with mass migration “our worst nightmares can come true. The West falls as it fails to see Europe being overrun.”²⁴⁹

Meanwhile, Denmark’s government proposed new laws, to be voted upon in the fall, that would radically restrict the behavior of people living in ghettoized neighborhoods that are predominantly Muslim; they include doubling the sentences for certain crimes committed in the listed neighborhoods and criminalizing taking children on extended trips to their countries of origin that could damage their “schooling, language and well-being.”²⁵⁰

A wild card that may shape this dynamic is the willingness of President Trump to openly support nationalist and anti-immigrant European politics. Trump has retweeted tweets from the deputy leader of Britain First, a far-right hate group.²⁵¹ Steve Bannon, the former chief executive of Trump’s campaign and White House adviser, plans to develop a group to promote a right-wing alliance of figures like Orbán.²⁵² Sam Brownback, the Trump-appointed U.S. ambassador for international religious freedom, has reportedly pushed for more sympathetic treatment of Tommy Robinson, a founder of the far-right English Defense League who is facing charges of disrupting a trial, and suggested that the Trump administration might otherwise intervene in the case.²⁵³ The impact of this new relationship between parts of the European far right and the Trump administration and its circles on the political fortunes of the far right is not clear, but it is a dynamic that must be watched.

As anti-immigrant parties and agendas gain strength, they risk escalating the sense of alienation among Europe’s already marginalized Muslim population, potentially contributing to further radicalization.In some cases anti-immigrant and anti-Muslim politics has been expressed through terrorism. In June 2018, France arrested 10 people suspected of plotting a terrorist attack against Muslims and who had acquired rifles, handguns and grenades.²⁵⁴ On June 19, 2017, a 48-year-old man killed one person and injured 10 others in a vehicle ramming near a mosque in north London, targeting Muslims during Ramadan.²⁵⁵ In 2017, Germany reported 950 anti-Muslim crimes with 33 injuries as a result of such crimes.²⁵⁶ While this far-right violence poses a significant threat on its own, it should also raise concerns about the potential for homegrown cycles of violence driven by polarization in European politics.

Geographic Proximity

The fourth factor that results in Europe facing a more severe threat is that Europe is simply closer in geography to the parts of the world where revolution and war have opened opportunities for jihadist organizing, while the United States is separated from these areas by thousands of miles and two oceans. As a result, the repercussions of instability in the Middle East and North Africa have more impact on Europe than on the United States.

Corrected at 2:20pm on September 11, 2018: A previous version of this report left out the surnames of Salah Abdeslam and Ibrahim El Bakraoui.

1. TATP: The Hydrogen Peroxide-Based Bomb of Choice²⁵⁷

Since 2014, there have been 14 attacks in the West involving explosives. Of those, six involved TATP, triacetone triperoxide, an explosive that has long been the bomb of choice for jihadists in the West due to the ease of acquiring the components to make it, as compared to military-grade explosives. It can be built using the common household ingredient hydrogen peroxide, which is used to bleach hair.

Table 1: Jihadist Attacks Involving TATP in the West

Table 2: Jihadist Attacks Involving Explosives Other Than TATP in the West

Making a TATP bomb is tricky because the ingredients are highly unstable and can explode if improperly handled. The danger of building TATP bombs without training can be seen in the case of Matthew Rugo and Curtis Jetton, 21-year-old roommates in Texas City, Texas.²⁵⁸ They didn’t have any bomb-making training and were manufacturing explosives in 2006 from concentrated bleach when their concoction blew up, killing Rugo and injuring Jetton. The pair had no political motives: They had just wanted to blow up vehicles for fun.

TATP therefore often indicates that a perpetrator received training or direction from a foreign terrorist group. Indeed, three of the six attacks involving TATP since 2014 — the 2015 Paris bombings, the 2016 bombings of the Brussels metro and airport by the same ISIS cell, and the 2017 bombing of an Ariana Grande concert in Manchester, England — were directed by ISIS. This accounts for half of the attacks known to have been directed by foreign terrorist organizations in the West since 2014 and all of the directed attacks that involved explosives.

The three other attacks since 2014 involving TATP — the September 2017 bombing at the Parsons Green tube station in London in which the bomb failed to fully explode, the August 2017 attacks in Barcelona where traces of TATP were found at a suspected bomb factory tied to the plot, and a June 2017 failed bombing of the Brussels metro that killed only the perpetrator —had no known operational link to ISIS.²⁵⁹ These attacks account for less than 5 percent of all inspired or enabled attacks and only a third of inspired or enabled attacks involving explosives.

Six ISIS-inspired attacks and two ISIS-enabled attack in the West since 2014 used other explosives. For example, Tashfeen Malik and Syed Rizwan Farook, who killed 14 people in San Bernardino, California, had built pipe bombs using Christmas lights and smokeless powder.²⁶⁰ The bomb recipe they used was learned from Inspire, the English-language propaganda magazine of Al-Qaeda in the Arabian Peninsula, whose article “Make a Bomb in the Kitchen of Your Mom” was also used by the Boston Marathon bombers.²⁶¹

2. The Rise of Vehicular Attacks²⁶²

Since 2014, vehicular ramming attacks have emerged as a key example of jihadist innovation on the lower end of sophistication, yet with a demonstrated capacity for causing mass casualties. The tactic, which had sporadic appearances in the past, has spread to those motivated by ideologies other than jihadism, becoming a staple of the modern terrorist threat to an extent not seen before.

Since 2014, there have been 16 vehicle ramming attacks in the West conducted by jihadists, which have killed a total of 145 people.²⁶³ On October 31, 2017, Sayfullo Saipov killed eight people in New York City when he drove a truck into a crowd — the first deadly vehicular ramming by a jihadist inside the United States.

Table 3: Jihadist Vehicular Ramming Attacks in the West

The death tolls from vehicular ramming attacks are highly variable. On July 14, 2016, Mohamed Lahouaiej Bouhlel drove a truck through a crowd gathered in the French city of Nice to celebrate Bastille Day. Bouhlel’s attack killed 86 people — the second most deadly jihadist attack in the West since 2014, surpassed only by the ISIS-directed and highly sophisticated 2015 Paris attacks. Yet unlike those attacks, Bouhlel’s attack lacked operational direction from ISIS.

On the other hand, numerous vehicular rammings have failed to kill anyone. For example, on September 30, 2017, Abdulahi Hasan Sharif, a 30-year-old Somali refugee, drove a truck into pedestrians, injuring four people but not killing anyone, after he also attacked a police officer in Edmonton, Canada.²⁶⁴

Despite the failure of some vehicular attacks to kill anyone, the potential for extremely deadly attacks with little need for coordination has made vehicular attacks particularly appealing to ISIS. None of the vehicular rammings were directed by ISIS, demonstrating the lack of training or specialization required to conduct such an attack. In September 2014, Abu Muhammad al-Adnani, the ISIS spokesman, called upon people in the West to conduct attacks with whatever means they had — specifically mentioning vehicular attacks.²⁶⁵

ISIS’ leaders are not the only ones to have taken notice of the wave of vehicular attacks and their impact. The tactic has been adopted by individuals in the West motivated by ideologies other than jihadism. In April 2018, Alek Minassian killed 10 people when he drove a van into a crowd in Toronto, Canada, after posting to Facebook that the attack was part of an “Incel Rebellion.”²⁶⁶ In June 2018, Gregory C. Wagner, a 58-year-old Republican councilman in Bell Acres, Pennsylvania, was charged with having driven his car into a crowd protesting a police shooting.²⁶⁷ In June 2017, a man killed one person and injured 11 when he rammed a vehicle into a group of Muslims outside a mosque in north London; the man allegedly shouted, “I want to kill all Muslims — I did my bit.” ²⁶⁸ Also, as noted above, a right-wing extremist killed a woman in Charlottesville, Virginia, in August 2017 when he rammed a car into a group of people protesting a white nationalist rally.

The potential for extremely deadly attacks with little need for coordination has made vehicular attacks particularly appealing to ISIS.

Vehicular attacks are not new. Al-Qaeda in the Arabian Peninsula called for such attacks in 2010, in Inspire magazine. In 2006, Mohammed Taheri-Azar injured nine people when he drove an SUV into people on the University of North Carolina Chapel Hill campus, and Palestinian militants have made frequent use of the tactic. However, such attacks have become a key part of today’s terrorist threat to an extent not seen before.

3. The Use of Armed Drones by Terrorist Groups

The United States should expect the use of armed drones by terrorist groups and other non-state actors to expand and remain a substantial aspect of the threat environment. Already, ISIS has made widespread use of drones in Iraq and Syria.

ISIS has deployed drones extensively. Eric Schmitt of the New York Times reported that over the course of December 2016 and January 2017, ISIS deployed more than 80 drones in combat in Iraq.²⁶⁹ In January 2017, ISIS announced in its newsletter al-Naba’ the establishment of the “Unmanned Aircraft of the Mujahideen,” an operational unit organized to engineer and deploy drones in combat.²⁷⁰ The terror network has been experimenting with drone technology since at least 2015, when Kurdish fighters in Syria shot down two small commercial drones reportedly belonging to the group — both of which were armed with explosives.²⁷¹ ISIS’ military defeats in Iraq and Syria dealt a substantial blow to its drone operations, but the ISIS campaign foreshadows a future in which non-state use of drones is common.²⁷²

The Houthi rebels in Yemen also have drones. In January 2017, a maritime drone operated by the Houthis crashed into a Saudi ship in the Red Sea, killing two Saudi sailors. Vice Adm. Kevin Donegan, commander of the U.S. Navy Fifth Fleet, described the drone to Defense News as a “remote-controlled boat of some kind” that was loaded with explosives.²⁷³

Though ISIS and the Houthis are the clearest cases of sustained armed drone campaigns by non-state actors, numerous other groups have used drones in combat or maintain the capability to do so. In January 2018, Russia claimed that one of its military bases in Syria was attacked by a swarm of improvised drones, though the responsible group is unknown.²⁷⁴ In July 2018, Venezuelan President Nicolas Maduro was the target of a botched assassination attempt utilizing two quadcopter drones rigged with explosives.²⁷⁵ Also in July 2018, drones carrying improvised explosive devices targeted the residence of the public safety secretary of Baja California, Mexico.²⁷⁶ In October 2017, Mexican Federal Police arrested four men with a quadcopter drone connected to an improvised explosive device, raising concern about the adoption of such techniques by drug cartels.²⁷⁷

Hezbollah and Hamas were early adopters of drone technology and maintain an armed drone capability. In 2004, Hezbollah flew a military-grade drone, reportedly acquired from Iran, over Israeli airspace.²⁷⁸ The Lebanese militant group also conducted strikes in Syria in 2014 with an armed drone and in 2016 with over-the-counter drones armed with small explosives.²⁷⁹

Terrorist use of drones, whether as part of military campaigns or for one-off attacks, is likely to continue and be an important site of terrorist innovation to monitor.

4. The Threat to Airports and Aviation

Jihadist terrorists continue to target airports and aviation. Three main threats to this sector deserve focus: attacks against aircraft involving explosives or other weapons taken past security; insider threats at airports that can allow terrorists to bypass security efforts; and attacks on unsecured parts of airports.

Attacks on aviation through the development of explosives that can be taken past security systems remain a persistent concern for the United States. In July 2018, Homeland Security Secretary Kirstjen Nielsen stated, “We still worry very much about aviation,” adding that the department continues to see terrorists “perfecting their opportunities to attack us through aviation.”²⁸⁰ In 2018, the Transportation Security Administration rolled out new, more extensive screening procedures for powders in carry-on luggage as a response to the foiled terrorist plot to bomb an Australian flight.²⁸¹

John Kelly, previously secretary of homeland security and now White House chief of staff, made airline and airport security a primary area of focus during his short tenure as secretary. In March 2017, the Department of Homeland Security imposed a ban on laptops, tablets and other devices larger than a mobile phone carried by passengers on flights coming from 10 Muslim-majority countries as a result of a believed ISIS threat; the ban was revoked in July.^{282 283} Al-Qaeda managed to transport explosives past security in the 2001 “shoe bomber” plot and again in the 2009 Christmas Day “underwear bomber” plot, and while neither attack succeeded in killing anyone, they could have killed hundreds if the explosives had detonated properly.

Though technical innovations allowing attackers to take explosives through security remain a major concern, jihadists have had more success in bypassing security by taking advantage of insider threats. On October 31, 2015, ISIS’ Sinai affiliate bombed a Russian airliner, killing all 224 people on board. ISIS reportedly relied upon employees at the airport to move the bomb past security and place it on the plane.²⁸⁴ In 2016, al-Shabaab bombed a flight out of Mogadishu airport in Somalia, reportedly relying on bombs concealed in laptops and on insiders who helped the bomber pass security. The bomb detonated early and killed only the bomber, but illustrates the threat of terrorist innovation and insiders who can enable bypassing of security.²⁸⁵

The threat of insider attacks is not restricted to flights outside the West. Since 9/11, there have been at least five Americans involved in jihadist activity who worked at airports. In the United Kingdom in 2010, British Airways IT expert Rajib Karim conspired with Anwar al-Awlaki to place a bomb on a plane headed to the United States. In correspondence with al-Awlaki, Karim wrote, “I do not know much about US I can work with the bros to find out the possibilities of shipping a package to a US-bound plane.”²⁸⁶

Jihadists have had more success in bypassing security by taking advantage of insider threats.

The third threat targets unsecured areas of airports for attacks. In 2017, there were two attacks with connections to jihadist ideology in unsecured locations at airports in the West; there have been no such incidents reported in 2018. In March 2017, Ziyed Ben Belgacem, a French national of Tunisian descent, was shot dead after assaulting a security guard at France’s Orly airport outside Paris. Belgacem, who had been in trouble with the law previously for a slew of offenses, likely radicalized in prison.²⁸⁷ The other case, mentioned previously, was Amor Ftouhi’s stabbing attack at the Flint, Michigan, airport in June 2017. Outside of the West, attacks on airports have also been common, often featuring more sophisticated and organized assault tactics.²⁸⁸

5. The Continued Absence of CBRN Attacks by Jihadists in the West ²⁸⁹

Weapons of mass destruction have continued to be absent in attacks by jihadist terrorists in the West. Of 91 attacks conducted by jihadists in the West since 2014, none involved chemical, biological, radiological or nuclear weapons (CBRN). In its 2018 report, Europol notes, “As in previous years, no terrorist attacks using chemical, biological, radiological or nuclear (CBRN) substances were recorded in the EU in 2017.”²⁹⁰ Of the 449 people in the United States accused of jihadist terrorism-related crimes since 9/11, none acquired such weapons.

Historically, al Qaeda-linked attackers have lacked backgrounds that would aid in the development of biological weapons. An examination of the educations of the 79 terrorists responsible for some of the worst anti-Western al-Qaeda attacks²⁹¹ — the World Trade Center bombing in 1993, the Africa embassy bombings in 1998, the 9/11 attacks of 2001, the Bali nightclub bombings in Indonesia in 2002 and the London bombings on July 7, 2005 — found that only one had obtained a degree in biology. One of the three masterminds of the Bali bombings, Aris Sumarsono, better known as Zulkarnaen, had studied biology at an Indonesian college and is among the top leaders of the al-Qaeda affiliated group Jemaah Islamiyah.²⁹²

Of 91 attacks conducted by jihadists in the West since 2014, none involved chemical, biological, radiological or nuclear weapons.

Other evidence points to a continued lack of sophistication when it comes to CBRN weapons. Europol noted that most of the propaganda urging CBRN attacks in Europe focused on dual-use toxic chemicals that could be obtained by unsophisticated plotters, rather than more sophisticated weapons.²⁹³ ISIS had the opportunity to acquire cobalt-60, a highly radioactive material that it could have used to build a radiological “dirty bomb” when it overran Mosul in 2014, but did not take advantage of the opportunity.²⁹⁴ Actual nuclear weapons remain well beyond the development capabilities of jihadist groups.

Terrorists instead continue to prefer the old standby weapons of bombs and firearms. The innovation that has occurred in weaponry and tactics used in attacks in the West has been almost entirely on the low end, through the adoption of vehicle rammings and stabbings. This is likely because such methods have proved themselves just as effective at creating mayhem and murder with far less need for technical know-how or training.

Despite the lack of CRBN attacks and greater innovation and interest on the low but deadly end of terrorist technology, jihadists have little compunction about using such weapons, as demonstrated by a series of recent plots.

For example, in 2018 there were at least two terrorism cases in the West with a connection to the biological toxin ricin. In June 2018, the United States arrested Waheba Dais, a 45-year-old woman and legal resident who helped spread instructional material regarding ricin online.²⁹⁵ Also in June 2018, German authorities arrested a Tunisian man who allegedly had successfully created ricin and was plotting to use it in an attack in Germany.²⁹⁶

The threat from jihadists interested in ricin should not be exaggerated. Ricin makes a poor mass casualty weapon, as it has to be ingested to be deadly.²⁹⁷ Though numerous militants have expressed interest in ricin or even produced it, there have been few if any deaths in ricin attacks: A 2010 Department of Homeland Security document lists only one such case — the 1978 assassination of Bulgarian dissident Georgi Markov in London.²⁹⁸

However, a more concerning recent plot involving chemical weapons is the 2017 Sydney plot in which Australian law enforcement discovered hydrogen sulfide precursors among the materials held by plotters in communication with a senior ISIS figure and virtual recruiter located in Syria.²⁹⁹

ISIS has also used chlorine on the battlefield in Syria and Iraq. Interestingly, despite this use of chemical weapons, it has seen little coverage in ISIS’ often detailed propaganda on its military operations, suggesting that using such weapons may be a low priority for ISIS with limited resonance in propaganda terms.³⁰⁰

Finally, it is worth noting that there is also a threat in the United States from chemical and biological weapons from individuals motivated by other ideologies. For example, William Krar and Judith Bruey, two anti-government extremists arrested in 2003, possessed precursor chemicals for hydrogen cyanide gas, while Michael Alan Crooker, another anti-government extremist, pleaded guilty in 2011 to possessing the biological toxin ricin and threatening an officer of the U.S. government.³⁰¹

6. Prison Releases

The scheduled release of large numbers of individuals convicted of terrorism-related crimes who have served their sentences, in addition to those previously released, could shape the terrorist threat in coming years. If these released individuals return to jihadist activity, they could reconstitute and expand the networks that helped fuel ISIS’ recruitment and attacks in the West.

Europe is at particular risk for such an occurrence, given the greater development and size of its jihadist networks to begin with and the existence there of serious prison radicalization problems.

An analysis by the Guardian found that 40 percent of terrorism sentences handed down in the United Kingdom between 2007 and 2016 will run out by the end of 2018, and additional convicted individuals may eligible for parole.³⁰² Among the British extremists reportedly eligible for parole by the end of 2018 is Anjem Choudary, a preacher and founder of the banned radical Islamist organization Al-Muhajiroun, who has been linked to several terrorism cases.³⁰³

According to France’s Ministry of Justice, France will release about 50 people sentenced for terrorism crimes and 400 individuals sentenced for other crimes but deemed to have radicalized in prison by the end of 2019.³⁰⁴

If these released individuals return to jihadist activity, they could reconstitute and expand the networks that helped fuel ISIS’ recruitment and attacks in the West.

In the United States, the problem is less severe — in accordance with the less severe state of the overall threat — but likely will also pose a challenge. At least 88 Americans who have been convicted of terrorism-related crimes since 9/11 have been released, according to New America’s research. An additional 72 are scheduled to be released by the end of 2025.

The individuals released by the United States so far range widely in terms of the seriousness of their crimes. They include Ali al-Marri, who was arrested in December 2001 but later held as an enemy combatant before being returned to the civilian justice system; he pleaded guilty to conspiracy to provide support to al-Qaeda, having been dispatched to the United States prior to 9/11 by Khalid Sheikh Mohammed.³⁰⁵ He was released in January 2015 and deported to Qatar.³⁰⁶ Those released also include members of the so-called Liberty City Seven, one of the most questionable FBI sting operations and one of the extremely small number of cases in which individuals accused of jihadist terrorist activity were acquitted.

Releases also include individuals convicted for more recent ISIS-related crimes. For example, Daniela Greene, an FBI translator who went to Syria and married Denis Cuspert, a German ISIS fighter and recruiter, was released in August 2016.³⁰⁷

So far, the United States has not seen a substantial threat from released jihadists, and individuals who have served their time should not be permanently ostracized from society due to a prior terrorism-related conviction. Some of the released individuals were convicted as a result of questionable informant-driven investigations while others appear to have been rehabilitated, and some have lent their knowledge and experience to efforts to counter the terrorist threat.³⁰⁸ For example, Jesse Morton, who was convicted in relation to his role in Revolution Muslim, through which he played an important role in jihadist recruitment in the United States, was released early and began working as an informant.³⁰⁹

However, the United States should be wary of overconfidence regarding the reintegration of released extremists. First, there is little if any developed infrastructure to support individuals upon their release.

There is little if any developed infrastructure to support individuals upon their release.

Even individuals who have cooperated substantially with the United States have struggled upon their release. Morton, for example, after having been released and working as an informant and then on counter-extremism issues, was arrested on charges related to having brought drugs to a meeting with a prostitute.³¹⁰ Bryant Neal Vinas, who joined al-Qaeda in Pakistan and who after his arrest cooperated with the government, providing extensive insight into the internal workings of al-Qaeda, upon his release was left without protection, struggled to find a job and became reliant on Medicaid and food stamps.³¹¹

The challenges of reintegration are not limited to those who offer extensive information or value to terrorism investigations. Paul Rockwood, who was released in September 2017 after having pleaded guilty to making false statements in a terrorism investigation related to his having drawn up a kill list, wrote to one of the authors, stating: “Because I am faced with so many uncertainties upon release, it is difficult for me to make any definitive plans. Not having a plan causes me considerable anxiety.”³¹² It is not surprising that Rockwood expressed concern. According to a court document filed in March 2016, a bit over a year before his release, he had only $5 in savings, was reliant upon a $1,000 monthly pension to support his wife and two children, and had $30,000 in debt.³¹³ Rockwood also noted that the Bureau of Prisons “has no deradicalization program(s) for inmates convicted of terror related offenses.”

Another individual, Craig Baxam, who pleaded guilty to having traveled to join Al Shabaab, had no permanent residence when scheduled for release and absconded from his halfway house.³¹⁴ According to court records, he had written a letter in which he threatened the government.³¹⁵

Second, though there is little evidence of a threat from U.S. individuals who have been released after serving time for terrorism charges, there are a small number of cases that point to problems related to the prison system that might escalate in the future. For example, Ali Muhammad Brown, who killed four people in a shooting spree across Washington state and New Jersey in 2014 inspired in part by jihadist ideology, was in the midst of a “downward spiral of criminality,” according to the judge in his case; he had been convicted of assault in 2008 and communication with a minor for immoral purposes in 2012 as well as bank fraud in 2005 and had served prison time.³¹⁶ The FBI believed that the bank fraud case was related to terrorism, but prosecutors failed to prove so in court.³¹⁷

Similarly, Elton Simpson, one of the attackers in the Garland, Texas, shooting in which only the perpetrators were killed, had been convicted in 2011 of making a false statement to investigators. The government alleged the false statement was terrorism-related, but Simpson was acquitted on that count as the judge ruled that the government had failed to prove that point.³¹⁸

Policymakers should not jump to conclusions regarding a threat from released extremists. Many pose no threat or are actively supporting government efforts to counter terrorism

These two cases, involving violence after convictions for crimes in which the government failed to prove an alleged terrorism nexus, point to the risks of recidivism and need for study of post-arrest paths of alleged extremists.

Another set of warning signs involves recent charges for activity within prisons. In March 2016, the United States charged Alex Hernandez, a 31-year-old inmate at the Old Colony Correctional Center in Bridgewater, Massachusetts, with threatening to kill the president. Hernandez allegedly told an undercover agent that he was “fighting to uphold the laws and structure of the caliphate in the Middle East.”³¹⁹ In 2017, the United States charged Clark Calloway, a 38-year-old ex-Marine, with federal firearms charges as a result of an investigation sparked by pro-ISIS statements on Facebook.³²⁰ According to the complaint in his case, Calloway repeatedly emphasized on Facebook his having served time in prison and stated that he had “met Al Qa‘ida members” there.³²¹ In another case, Casey Charles Spain pleaded guilty in 2017 to possession of a firearm as a felon, and according to his plea had radicalized while in prison, swearing loyalty to ISIS’ leader.³²²

Policymakers should not jump to conclusions regarding a threat from released extremists. Many pose no threat or are actively supporting government efforts to counter terrorism. In the past, claims regarding prison radicalization in the United States have often proved to be overblown. However, given the larger number of individuals passing through the justice system on terrorism charges in recent years and the changes in the nature of the threat, a reassessment of efforts at deradicalization, alternatives to incarceration and reintegration efforts for extremists upon release is warranted.

At the same time, a reassessment is warranted to evaluate whether the government is doing enough to enable released extremists to reenter society and live their lives at a time when a criminal conviction for crimes with much lesser stigma than terrorism can exert a profound and destabilizing influence upon an individual’s life, even after the person has reformed. This will be particularly important in an age where young children and other vulnerable individuals have become increasingly the subject of terrorism investigations and the target of terrorist recruitment.

The territorial collapse of ISIS in Syria and Iraq and the resultant degradation of its external attack capabilities provide the West with breathing room in its confrontation with terrorism. However, the larger jihadist movement remains strong, and the terrorist threat remains persistent and in flux. Policymakers should take the opportunity provided by the receding threat from ISIS to debate and develop counterterrorism strategies that address the new threat environment rather than resting on their laurels until a new group, or a resurgent ISIS or al-Qaeda, once again succeeds in directing a major attack in the West.

Here are some ideas about what should be done:

• The president and his National Security Council should release a public counterterrorism strategy. While the Trump administration has released a general National Security Strategy, it has not yet released a specific statement of its strategy for counterterrorism. As New America fellow and former NSC senior director for counterterrorism Joshua Geltzer and Center for a New American Security adjunct senior fellow Stephen Tankel argue, “While one can surmise the basic aspects of Trump’s approach to counterterrorism and identify potential pitfalls ahead, the absence of an official, reviewable strategy makes matters worse.”³²³ Releasing an official strategy document would go a long way toward both clarifying the Trump administration’s policies and enabling a much-needed public debate on how best to counter terrorism in a sustainable manner.
• The United States should conduct an assessment and audit of the amount of money spent on counterterrorism efforts since the 9/11 attacks. One of the core stated objectives of al-Qaeda was to drain U.S. resources. That there is no official accounting of the money spent — according to the Stimson Center, it may be as high as 15 percent of discretionary spending — is extremely concerning, given the strategic implications of waste and the potential that any savings could be applied to more critical issues.³²⁴
• Congress should debate and pass a new Authorization for Use of Military Force (AUMF). The United States currently relies on a 17-year-old authorization — along with claims of imminent threat — for the legal basis of its counterterrorism operations. The threat the United States faces today is substantially transformed from what the 2001 AUMF was designed to respond to. There are real questions as to whether a group like ISIS, which split off from al-Qaeda and waged war against it, can be covered accurately under the 2001 AUMF. These problems are likely to increase further as the years pass.
• The White House should draft and publicly release a report detailing the Trump administration’s policies regarding counterterrorism strikes similar to the Presidential Policy Guidance released by the Obama administration in 2016. The Trump administration has reportedly made numerous substantial policy changes to the processes regarding counterterrorism strikes. Yet the administration has not released information on these changes, representing a step backward for transparency since the end of the Obama administration. Having a transparent accounting of when, why and how the United States conducts counterterrorism strikes abroad is necessary for policymakers and the public to be able to assess the weighty strategic and moral questions involved in the United States’ continuing counterterrorism wars.
• The Pentagon should provide a public accounting of the countries where the United States is conducting counterterrorism operations and better communicate the existence and role of such operations to legislators and the public. Congress should uphold its responsibility to pay attention to where and why the U.S. is engaged in military action. On October 4, 2017, ISIS in the Greater Sahara ambushed U.S. forces operating in Niger, killing four Americans.³²⁵ Following the ambush, key U.S. senators expressed surprise regarding the extent of American military involvement in Niger.³²⁶ Senator Lindsey Graham stated, “I didn’t know there was 1,000 troops in Niger,” adding, “We don’t know exactly where we’re at in the world, militarily, and what we’re doing.” Senate Minority Leader Chuck Schumer also said he did not know about the presence of U.S. troops in Niger. While such statements must be taken with a grain of salt, as the Pentagon said it did indeed brief lawmakers on the U.S. presence and other representatives confirmed that they knew about the presence, the claims of ignorance reveal a lack of sustained oversight and a failure of many in Congress to fulfill their duty to oversee American military action.

  At the same time, the Pentagon must provide, to the extent possible, accurate and public data on where U.S. troops are operating. In December 2017, the Pentagon announced that there were 2,000 U.S. troops deployed in Syria — four times the largest previously released count, even though the number had been declining for months.³²⁷ The announcement came as a result of a review initiated by Defense Secretary James Mattis of substantial discrepancies between public and actual troop numbers.³²⁸ The Pentagon should make a greater effort to provide an accurate picture of where and how American forces are operating. That key congressional representatives, let alone the public, claim ignorance on these questions is a failure of communication as well as a failure of Congress to exercise oversight.

• Congress should expand oversight of American counterterrorism strikes and the Pentagon should expand protections against civilian casualties. A deep, on-the-ground investigation into American counter-ISIS airstrikes in Iraq by New America fellows Azmat Khan and Anand Gopal “found that one in five of the coalition strikes we identified resulted in civilian death, a rate more than 31 times that acknowledged by the coalition.”³²⁹ The investigation found that in addition, many of the strikes that caused civilian deaths were the product of incorrect intelligence. The investigation has resulted in calls for greater oversight and review of the targeting process. In the New York Times, Senator Patrick Leahy of Vermont wrote, “These are solvable problems. … This should start with the secretary of defense immediately commissioning a team of experts, including military and intelligence officers and representatives of organizations like the Center for Civilians in Conflict, which has extensive experience in documenting civilian casualties. This team should conduct a comprehensive analysis of every aspect of the current procedures for identifying and verifying potential targets and make recommendations for improvement.”³³⁰ Leahy has also called for greater disbursement of funds for condolence payments to families of civilians killed by American airstrikes, which until the aforementioned investigation had not been disbursed in a single case of an anti-ISIS strike, and greater transparency regarding the conduct of strikes. All of these recommendations should be pursued by the Pentagon.
• The United States should seek to deescalate conflicts in the Middle East and North Africa. Al-Qaeda, ISIS and other jihadist groups have drawn upon the escalation of conflict in the Middle East — whether the sectarian civil war that followed the 2003 invasion of Iraq, the chaos that followed the fall of Libyan leader Muammar Ghaddafi, or ISIS’ rise amid the Syrian civil war — to fuel their recruitment and expansion. While the escalation of conflict in the Middle East is driven by a number of factors, not all of which the United States can influence, and while there may be cases where military action is required, in general the United States should strenuously seek to avoid initiating new conflicts or escalating ongoing ones while simultaneously seeking to bring ongoing conflicts to an end.
• The president should end the travel ban. As described earlier in this report, the travel ban would not have prevented a single deadly attack inside the United States since 9/11, or the 9/11 attacks themselves. It is too broad a tool that simultaneously reflects a misunderstanding of the homegrown nature of the threat faced by the United States. Moreover, its promulgation has disrupted relationships and partnerships that play important roles in the U.S. counterterrorism effort. For example, the inclusion of Chad reportedly strained U.S. relations with an important partner in the effort against Boko Haram, perhaps contributing to Chad’s decision to withdraw troops from the fight against the terrorist group in Niger.³³¹ The initial inclusion of Iraq as part of the travel ban also strained relations in the midst of counter-ISIS operations.³³² Furthermore, the ban strains the U.S. government’s relations with American Muslim communities.
• The U.S. government should build trust with rather than alienate Muslim communities. The past few years have brought a marked increase in tension between American Muslim communities and the government. In particular, 2016 and 2017 were characterized by an increase in anti-Muslim political activity, driven in large part by the adoption of anti-Muslim messages by political campaigns — most notably that of Donald Trump, according to data collected by New America’s Muslim Diaspora Initiative.³³³ For example, the Trump administration implemented a travel ban modeled on Trump’s campaign calls for a Muslim ban. These new strains build upon earlier tensions over the role and nature of surveillance and other U.S. policies in the war on terrorism.

  The new tension has already demonstrated an impact on U.S. counterterrorism efforts. The Minneapolis Somali nonprofit Ka Joog declined a $500,000 grant from a federal Countering Violent Extremism program, explicitly citing “an unofficial war on Muslim Americans” by the Trump administration.³³⁴ While the merits of particular Countering Violent Extremism programs are certainly up for debate, such refusals illustrate the expanding distrust and hesitancy to partner with the government and reflect a larger challenge to partnerships.

  Good relations and partnerships between American Muslim communities and the government can play a key role in countering jihadist terrorism. At the 2018 Aspen Security Forum, FBI Director Christopher Wray emphasized the importance of trust, stating, “There’s almost always a neighbor, a family member, a friend, a coworker, somebody who observed that [the process of radicalization], and we need to be in a situation where people trust us enough to, as you say, see something, say something.”³³⁵ In an ongoing study of some 80 terrorism cases in the U.S. since 2009, the FBI found that leakage — the revelation of details about impending acts — happened more than 80 percent of the time.³³⁶ Those to whom information was leaked, termed “bystanders,” were broken down by the FBI into peers, family members, authority figures and strangers. FBI analysts found an average of three bystanders per case, and in one case as many as 14. Some bystanders saw radicalization behavior. Others saw actual plotting and planning, such as the accumulation of weapons, self-educating about how to make explosives or preparations to travel overseas for terrorist training. Analysts graphed out the bystanders who were most likely to come forward with information versus those least likely to do so. Peers were aware of the most concerning information, but they were the least likely to volunteer it. Family members were often aware of both radicalization and planning, but they came forward less often than authority figures such as college professors, supervisors, military commanders or clerics. These figures were reasonably likely to offer information but were more aware of a suspect’s radical sympathies than of any actual plotting. Strangers were the most likely to come forward, which can be helpful. However, they made up only 5 percent of the bystanders with useful information about a suspect. The lesson of the FBI study of terrorism cases is that the most useful information comes from peers and family members. As a result, policies and rhetoric that undermine trust between Muslim (and other) communities and the government risk harming counterterrorism efforts.

• The United States should relentlessly hammer home the message that while ISIS has positioned itself as the defender of Muslims, its victims are overwhelmingly Muslim. U.S. officials should support efforts to catalogue the extent of ISIS’ crimes and governance failures.
• The United States should conduct a review and assessment of alternatives to prison time for convicted jihadists, efforts to prevent radicalization in prison, and the state of preparations for release for those convicted of terrorism-related crimes. As many extremists begin to be released from prison, and with an unprecedented number of terrorism cases in recent years — in large part due to the rise of ISIS — a review and reconsideration of the approach to incarceration of terrorists is needed. This issue is compounded by several terrorism investigations involving children, for whom the imposition of long prison sentences raises significant moral issues.