**FILE** White House workers walk on the roof of the White House on Sept. 12, 2012, after lowering the flag to half-staff for the death of U.S. ambassador to Libya Christopher Stevens. (Associated Press)

Photo by: Evan Vucci

**FILE** White House workers walk on the roof of the White House on Sept. 12, 2012, after lowering the flag to half-staff for the death of U.S. ambassador to Libya Christopher Stevens. (Associated Press)