President Barack Obama puts his hand on the shoulder of outgoing Defense Secretary Robert Gates, as he introduced a reworked national security team, Thursday, April 28, 2011, in the East Room of the White House in Washington. From left are, top commander-designate for U.S. forces in Afghanistan, Marine Corps Lt. Gen. John Allen; CIA Director-nominee Gen. David Petraeus; Defense Secretary-nominee Leon Panetta; Gates; the president; and Vice President Joe Biden. (AP Photo/Charles Dharapak) Read more: