9/11/2012 - U.S. military members, alongside Federal Fire Department members, pay their respects during a Sept. 11th Remembrance Ceremony on Joint Base Pearl Harbor-Hickam, Hawaii, Sept. 11, 2012. This year marks the 11th anniversary of the attacks on the World Trade Center, the Pentagon, and the crash in Shanksville, Pennsylvania. (U.S. Air Force photo/Senior Airman Lauren Main)

9/11/2012 - U.S. military members, alongside Federal Fire Department members, pay their respects during a Sept. 11th Remembrance Ceremony on Joint Base Pearl Harbor-Hickam, Hawaii, Sept. 11, 2012. This year marks the 11th anniversary of the attacks on the World Trade Center, the Pentagon, and the crash in Shanksville, Pennsylvania. (U.S. Air Force photo/Senior Airman Lauren Main)

9/11/2012 - Federal Fire Department members, alongside U.S. military members, pay their respects during a Sept. 11th Remembrance Ceremony on Joint Base Pearl Harbor-Hickam, Hawaii, Sept. 11, 2012. This year marks the 11th anniversary of the attacks on the World Trade Center, the Pentagon, and the crash in Shanksville, Pennsylvania. (U.S. Air Force photo/Senior Airman Lauren Main)

9/11/2012 - Federal Fire Department members, alongside U.S. military members, pay their respects during a Sept. 11th Remembrance Ceremony on Joint Base Pearl Harbor-Hickam, Hawaii, Sept. 11, 2012. This year marks the 11th anniversary of the attacks on the World Trade Center, the Pentagon, and the crash in Shanksville, Pennsylvania. (U.S. Air Force photo/Senior Airman Lauren Main)