 Rood also served as Acting Under Secretary of State for Arms Control and International Security from September 2007 to January 2009, and as Assistant Secretary of State for International Security and Nonproliferation from October 2006 to September 2007.He served at the United States National Security Council as special assistant to the president and senior director of Counterproliferation and Director of Proliferation Strategy for Counterproliferation in Homeland Defense.Rood served at the Defense Department as Deputy Assistant Secretary of Defense for Forces Policy, and at the Central Intelligence Agency as an analyst following missile programs in foreign countries.