Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, testifies on Capitol Hill in Washington on Thursday, Feb. 7, 2013, before the Senate Armed Services Committee hearing on the Pentagon's role in responding to the attack last year on the U.S. Consulate in Benghazi, Libya. (AP Photo/J. Scott Applewhite)

Photo by: J. Scott Applewhite

Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, testifies on Capitol Hill in Washington on Thursday, Feb. 7, 2013, before the Senate Armed Services Committee hearing on the Pentagon's role in responding to the attack last year on the U.S. Consulate in Benghazi, Libya. (AP Photo/J. Scott Applewhite)