President George W. Bush and Chairman of the Joint Chiefs of Staff Adm. Mike Mullen, U.S. Navy, salute the flag during the playing of the national anthem during the Pentagon Memorial dedication ceremony on Sept. 11, 2008. 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.