Vice President Joe Biden, center, and Interior Secretary Ken Salazar, right, walk in front of The Wall of Names, containing the names of the 40 passengers and crew of Flight 93, as they

 

              Vice President Joe Biden, center, and Interior Secretary Ken Salazar, right, walk in front of The Wall of Names, containing the names of the 40 passengers and crew of Flight 93, as they
Vice President Joe Biden, center, and Interior Secretary Ken Salazar, right, walk in front of The Wall of Names, containing the names of the 40 passengers and crew of Flight 93, as they arrive for a memorial service at the Flight 93 National Memorial in Shanksville, Pa., Tuesday, Sept. 11, 2012. (AP Photo/Gene J. Puskar)