President Barack Obama speaks in the East Room of the White House in Washington, Monday, Jan. 7, 2013. (AP Photo)
© Deputy National Security Adviser for Homeland Security and Counterterrorism John Brennan briefs reporters at the White House in Washington, in this Oct. 29, 2010 file photo.
© This Dec, 18, 2008 file photo shows then-Nebraska Sen. Chuck Hagel in Omaha, Neb. President Barack Obama will nominate Hagel as his next defense secretary, a senior administration official said Sunday, Jan. 6, 2013.