President Barack Obama shakes hands with former Navy Commander Zoe Dunning, as Joint Chiefs Chairman Adm. Mike Mullen, second from right, and former Marine Staff Sgt. Eric Alva applaud during a signing ceremony for “don’t ask, don’t tell” repeal legislation that would allow gays to serve openly in the military, Wednesday, Dec. 22, 2010, at the Interior Department in Washington. (AP Photo/Evan Vucci)