TOP LEADERS Left to right, Army Gen. Martin E. Dempsey, Defense Secretary Leon E. Panetta, Vice President Joe Biden, President Barack Obama and Navy Adm. Mike Mullen, outgoing chairman of the Joint Chiefs of Staff, observe the passing of the honor guard at the Chairman of the Joint Chiefs of Staff change of responsibility ceremony on Joint Base Myer-Henderson Hall, Va., Sept. 30, 2011. Dempsey succeeded Mullen, who is is retiring after 43 years of service. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 645010-Y-CIJ57-590.jpg Photo Gallery