The official party watches as the first inscribed memorial unit is unveiled at the Pentagon Memorial Sept. 11 in Alexandria, Va. The national memorial is the first to be dedicated to those killed at the Pentagon on Sept. 11, 2001. The site contains 184 inscribed memorial units honoring the 59 people aboard American Airlines Flight 77 and the 125 in the building who lost their lives that day. (Defense Department photo/Cherie Cullen)