COMMEMORATING 9/11 Defense Secretary Leon E. Panetta, President Barack Obama and Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, render honors as the national anthem plays during the ceremony to commemorate the 11th anniversary of the 9/11 terrorist attacks at the Pentagon, Sept. 11, 2012. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 113728-F-HRS47-835.jpg Photo Gallery