Anniversary of Sept. 11th Attacks Marked At Pentagon
ARLINGTON, VA – SEPTEMBER 11: U.S. President Barack Obama lays a wreath during a memorial service at the Pentagon as Chairman of the Joint Chiefs of Staff Navy Admiral Mike Mullen looks on, September 11, 2011 in Arlington, Virginia. First lady Michelle Obama, Secretary of Defense Leon E. Panetta and Vice President Joseph R. Biden also attended the service at the Pentagon Memorial to commemorate the 10th anniversary the September 11, 2001 terrorist attacks on the United States. (Photo by Joshua Roberts-Pool/Getty Images)