** FILE ** The American flag flies at half-staff over the White House on Sept. 15, 2012, in honor of those who died when an angry mob stormed the U.S. Consulate in Libya's eastern city of Benghazi on Sept. 11, 2012. The U.S. Ambassador to Libya, Christopher Stevens, was killed along with three other Americans. (AP Photo/J. Scott Applewhite)

Photo by: J. Scott Applewhite

** FILE ** The American flag flies at half-staff over the White House on Sept. 15, 2012, in honor of those who died when an angry mob stormed the U.S. Consulate in Libya's eastern city of Benghazi on Sept. 11, 2012. The U.S. Ambassador to Libya, Christopher Stevens, was killed along with three other Americans. (AP Photo/J. Scott Applewhite)