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Ambassador Donald A. Mahley


BA 1964, Philosophy

Retired from full-time duty, Ambassador Mahley continues to serve as a special negotiator for Nonproliferation. Currently, he is representing the United States at the discussions in the United Nations on an Arms Trade Treaty. He is also serving as a member of the United Nations Secretary General’s Disarmament Advisory Board.

Ambassador Mahley served as the Acting Deputy Assistant Secretary for Threat Reduction, Export Controls and Negotiations.  As such, he had the responsibility for chemical and biological weapons threat reduction, missile threat reduction, conventional weapons threat reduction, and export controls.

Previously, Ambassador Mahley was the Deputy Assistant Secretary for Arms Control Implementation in the Arms Control Bureau of the Department of State. He served as the Special Negotiator for Chemical and Biological Arms Control issues from April 1999 to September 2002. Ambassador Mahley headed the United States Delegation to Biological Weapons Convention activities and was the Managing Director of the United States National Authority for implementation of the Chemical Weapons convention from 1997 to 2008. From 1993 until 1999, Ambassador Mahley served as Deputy Assistant Director and Acting Assistant Director of the Multilateral Affairs Bureau of the Arms Control and Disarmament Agency. While still in military service, from 1990-1992, he served as Associate Assistant Director of the Multilateral Affairs Bureau and led U.S. efforts to conclude the Chemical Weapons Convention. Prior to his term in ACDA, Ambassador Mahley served six years (1984-1990) as Director of Defense Policy and Arms control on the National Security Council Staff.  He arrived at the NSC after four years in the U.S. Mission to NATO, having served as Deputy Director of the Defense Plans Division for the U.S. Ambassador to NATO.

Ambassador Mahley is a retired United States Army officer, Ordnance, in the rank of Colonel. He served in Viet Nam, Turkey, and Belgium during his active duty with the United States Army, and successfully held three command positions during his military career. He also served as an Assistant Professor of Social Sciences at the United States Military Academy and an Associate Professor of Military Strategy at the National War College.

Mahley’s favorite American diplomat is General of the Army, George C. Marshall. Mahley credits time spent in intercollegiate debate classes at Purdue with his military success. He notes, “Military Academy graduates get engineering training, where everything is black and white, right and wrong. It’s important for Army officers to know there’s not always necessarily a right answer.”