Has served with: Office of Secretary of Defense; Office of Secretary of the Navy; US Embassy in Moscow. Currently: Professor of International Relations, American University; Senior Research Associate, Changing Character of War Programme, University of Oxford. Former: Director, War and Statecraft, US National War College, Washington, DC; Director of Studies, Oxford-Leverhulme Programme on Changing Character of War, Nuffield College, University of Oxford; and Specialist in Terrorism, US Congressional Research Service, Library of Congress. Author, How Terrorism Ends: Understanding the Decline and Demise of Terrorist Campaigns (2010); Ending Terrorism - Lessons for Defeating Al-Qaeda, International Institute for Strategic Studies, London (2008); widely published, especially on how conflicts end.