How should the U.S. respond to Steven Sotloff’s killing?

For reaction, Judy Woodruff talks to Charles Sennott of The GroundTruth Project. Then, former National Security Council staff Lt. Col. Douglas Ollivant (Ret.), former Counterterrorism Official Daniel Benjamin and former State Department official Anne-Marie Slaughter discuss how the killing of Steven Sotloff affects U.S. policy toward the Islamic State group.