U.S. Defense Secretary Robert Gates (L-R), President Barack Obama and Chairman of the Joint Chiefs of Staff U.S. Navy Admiral Michael Mullen salute during a march-in-review by soldiers in Colonial-style uniforms during Gates’s farewell ceremony at the Pentagon in Arlington, Virginia, June 30, 2011. Gates is stepping down after four and a half years as the U.S. defense chief. REUTERS/Jonathan Ernst (UNITED STATES – Tags: POLITICS MILITARY)