FILE - In this June 15, 2011, file photo, then-Secretary of Defense Robert Gates testifies regarding the Department of Defense Fiscal Year 2012 budget request before the Senate Appropriations Committee Subcommittee on Defense on Capitol Hill in Washington. Gates asserts in a new memoir that President Barack Obama grew frustrated with U.S. policy in Afghanistan and that Vice President Joe Biden has been wrong on nearly every foreign policy and national security issue. He also accuses members of Congress of inquisition-like treatment of administration officials.  (AP Photo/Charles Dharapak, File)

FILE - In this June 15, 2011, file photo, then-Secretary of Defense Robert Gates testifies regarding the Department of Defense Fiscal Year 2012 budget request before the Senate Appropriations Committee Subcommittee on Defense on Capitol Hill in Washington. Gates asserts in a new memoir that President Barack Obama grew frustrated with U.S. policy in Afghanistan and that Vice President Joe Biden has been wrong on nearly every foreign policy and national security issue. He also accuses members of Congress of inquisition-like treatment of administration officials. (AP Photo/Charles Dharapak, File)