Leon Panetta became the 23rd Defense Secretary during a swearing-in ceremony at the Pentagon, July 1, 2011. Panetta, who had been CIA director since February 2009, replaced Robert Gates, who retired after leading the Pentagon since December 2006. Here, DOD General Counsel Jeh Johnson (left) administers the oath of office to Panetta.
DOD photo by Air Force TSgt. Jacob N. Bailey