Graham Allison is director of the Belfer Center for Science and International Affairs and Douglas Dillon Professor of Government at Harvard’s John F. Kennedy School of Government, where he was the dean from 1977 to 1989. He also served as special advisor to the Secretary of Defense under President Reagan and Assistant Secretary of Defense for Policy and Plans under President Clinton. He was a member of the Defense Policy Board for Secretaries Weinberger, Carlucci, Cheney, Aspin, Perry, and Cohen. His publications include Essence of Decision: Explaining the Cuban Missile Crisis, and Realizing Human Rights: Moving from Inspiration to Impact. His most recent book is Nuclear Terrorism: The Ultimate Preventable Catastrophe.