Sen. Bob Corker, R-Tenn., right, confers with Sen. Johnny Isakson, R-Ga., left, as they listen to testimony from State Department officials after an independent review panel said this week that serious bureaucratic mismanagement was responsible for inadequate security at the mission in Benghazi, Libya, where the U.S. ambassador and three other Americans were killed on Sept. 11, on Capitol Hill in Washington, Thursday, Dec. 20, 2012. Deputy Secretary of State Thomas Nides, who is in charge of management, and State Department Deputy Secretary of State William Burns, who is in charge of policy, appeared in place of Secretary of State Hillary Rodham Clinton who had been scheduled to testify but canceled after fainting and sustaining a concussion last week. (AP Photo/J. Scott Applewhite)