This month marks the 80th anniversary of an iconic historic event: the Nazi regime’s remilitarization of the German Rhineland in 1936. While the Rhineland crisis is often rolled into the longer chain of events that marked the rise of German power in the 1930s, this particular moment has captured the imagination of countless postwar observers who see it as the golden —and lost—opportunity to stop Adolf Hitler and his murderous ambitions. Winston Churchill fed this view in his wartime memoirs; he called World War II “The Unnecessary War,” concluding “there never was a war more easy to stop than that which has just wrecked what was left of the world from the previous struggle.” If valid, this claim is shocking: that the most costly war in history was also a war that could have been prevented.
While much has changed in the world since 1945, World War II is rarely seen as merely a tragedy isolated in time. Today, when speaking of, say, Russia or Iran, we treat the 1930s as a reservoir of lessons that can be pulled forward in time to help us learn how we might avoid the horrors suffered by earlier generations. So what does the Rhineland crisis have to teach us?
In the days after German soldiers rolled westward across the Rhine River in March 1936, French Foreign Minister Pierre Étienne Flandin called for “urgent, brutal, decisive measures” to turn back this rapid advance in German power. Flandin was calling for preventive war against Nazi Germany. Among the options states have for countering potential threats, none are as bold or brutal as preventive war. In simple terms, the goal is to seize the initiative and physically beat back the rising power of a rival with military force. This is not about defense against actual aggression, or even a first strike to preempt an adversary’s imminent attack. It is the choice to strike against a rival as it grows stronger, to avoid the mere possibility that it might one day be strong enough to pose a danger.
The allure of preventive war is found in its promise to eliminate the looming security problem at its source. Those observing a growing rival are living with the danger. Their safety rests precariously on their rival’s ambitions, on its decisions, and on the risks it is willing to run. Preventive war promises deliverance from that danger. It gives those who initiate war the sense that their safety now rests on their own decisions, not merely on their ability to fight and defend if the rival chooses to lash out.
This is what Flandin hoped to achieve when he called for “decisive measures” in 1936. And given what we know France faced in the years that followed, the wisdom of turning to the preventive war option to solve the problem seems obvious. British leaders, however, refused to support the French call for preventive attack, and so the proposal died. To this day, the British decision is condemned as a grave mistake, a lost opportunity to eliminate the German threat before the brutality of Nazi aggression erupted.
This verdict turns the 1930s into a story of heroes and goats. Churchill is remembered as one of the heroes, standing among that small group of allegedly prescient leaders who warned that each move Hitler made was one more step in a methodical plan of resurrection and conquest, and who insisted on the forceful action demanded of the moment to strangle Germany’s aspirations before it was too late. The goats in this telling of the story are those leaders who lacked the wisdom to see the future or listen to those like Churchill who could.
Today, the 1930s serve as a rallying cry, prodding future generations into mustering the courage and the forces necessary to take similarly “urgent, brutal, decisive” measures to suppress rising threats in our own time—against Iraq, Iran, and North Korea, for example—before it is too late to stop new catastrophes. But the lessons of the 1930s, and the Rhineland crisis specifically, are not as crystal clear as the typical narrative suggests.
In reality, the Rhineland crisis does not illuminate sharp contrasts between folly and wisdom, between the heroes and the goats of history. Instead, it shines a glaring light on the limited human capacity for seeing the future with real clarity. The ancient Greeks recognized these limitations, and in turn they revered the gift of “prognosis,” that ability to accurately anticipate the future that few individuals seemed to possess. In their mythology, the Greeks told stories of the Titan named Prometheus, whose foresight was the source of his wisdom.
Unfortunately, Prometheans are a rare breed in Greek myths, and virtually non-existent in real life. As the Danish philosopher Soren Kierkegaard eloquently reminds us, life is only “understood backwards,” but it is “lived forward.” This simple observation captures a tragic reality. Every leader who has had responsibility for making decisions today about how to deal with potential threats of the future has been caught in that unavoidable condition of having little clarity on how the future will unfold. Modern scholars have discovered that even experts in the field of international relations have a poor track record for predicting the future with precision.
This is a particularly serious limitation when it comes to shifting power and preventive war. By definition, the temptation of preventive war bubbles up in response to fear of the future, and the intensity of the temptation to pull the trigger will spike when leaders grab on to worst-case predictions about aggressive behavior as their rivals’ offensive capabilities grow. Fear is an essential survival mechanism, provoking the action necessary to escape or neutralize threats before the damage is done. But fear is a two-edged sword. It can also lead to overreaction, misjudgment, and tragedy. The difference hinges on how accurately we anticipate the future.
But can leaders see the future clearly enough to justify launching such wars with true confidence that the risks are essential for long-term defense? Are they actually preventing future aggression and more costly armed conflict? Or are they simply bringing on the costs and unintended dangers of war unnecessarily?
Consider this sobering example. In August 1950, the American Secretary of the Navy stood before a large crowd gathered at the Charlestown Navy Yard in Boston to celebrate its 150th birthday. He chose this otherwise happy occasion to issue a warning that was familiar to Americans in the early Cold War: “We can’t just sit by and be bled white by the communist nations. There may be a climax to this situation—an all-out contest.” The Soviets “are going to aggress when and where it suits them,” he said. “If we sit idly by, we will suffer.” In April 1950, NSC 68, the most important early Cold War assessment of the future threat, predicted that in just four years the USSR would have an atomic arsenal and a bomber force large enough to execute a decisive attack that put America’s very survival at risk. Once the Soviets reached this threshold in its capabilities, NSC 68 warned, “The Kremlin might be tempted to strike swiftly and with stealth.”
A parade of strategic thinkers in the military, in academia, and among pundits joined Secretary Matthews in his call for preventive war to save America from this horrible future while there was still time. Presidents Truman and Eisenhower, however, rejected the preventive war option. Who was the hero, who was the goat, in this particular story? It is only in hindsight that we can definitively answer that question, knowing that the peaceful end to both the Cold War and the USSR would have made preventive war a tragically unnecessary decision.
Or consider the problem of North Korea. In 1994, as the Clinton administration debated its options for responding to North Korea’s first threat to withdraw from the NPT, Secretary of Defense William Perry urged the president to order airstrikes against its nuclear facilities at Yongbyon. He justified this bold recommendation with a warning: “whatever dangers there are in” the preventive attack option, “these dangers are going to be compounded two to three years from now when…they’re producing bombs at the rate of a dozen a year.” In a Washington Post editorial in June 2006 and in Time magazine in July, Perry and current Secretary of Defense Ashton Carter chastised the Bush administration for its preoccupation with the Middle East while the North Korean threat grew. As North Korea prepared to conduct a test launch of a long-range missile, Perry and Carter called for military strikes to destroy the missile at its launch site, using the same preventive logic mobilized for war against Iraq a few years earlier.
Was Secretary Perry a hero for advocating preventive attack against North Korea in 1994? Was President Clinton a goat for rejecting his advice? If North Korea ends up lobbing nuclear weapons against the American homeland, or against Tokyo or Seoul in some future war, there will be a deafening outcry about Clinton’s horrible mistake, rendered in the same terms used to condemn British leaders of 1936. If, however, North Korea collapses peacefully and we escape such a conflagration, we will look back with relief and gratitude for Clinton’s restraint in the face of rising fear. But today, it’s impossible to state with finality what the future judgment on this decision will be.
The dilemma was no different for those trying to predict the future in 1936 while wrestling with their options for responding to the steady recovery of German power. In that allegedly golden moment for preventive war, there were no clear heroes or goats. Prometheus was a myth, not a man, and it is men and women, with our limited vision, that make decisions about preventive war.
No one of stature in Great Britain called for backing France in a preventive war to suppress German power. This includes Winston Churchill and his fellow anti-appeasers, who took an increasingly tough stand against Germany as the years went by and the near future truly began to crystalize. In his famous 1946 “Iron Curtain” speech on the challenge of meeting rising Soviet power, Churchill claimed that in the 1930s he “saw it all coming.” But in fact, Churchill too was struggling with the unavoidably cloudy future, a future that was too obscure in its details to justify initiating another great war with Germany. Like Prometheus, Churchill is revered for his foresight. The real lesson of the Rhineland, though, is that it’s only hindsight that led him to his confident postwar assertions about this particular mistake.