FBI Director Robert Mueller, Director of National Intelligence James Clapper and CIA Director David Petraeus appear before the Senate Select Committee on Intelligence on Capitol Hill on Tuesday. Win McNamee/Getty Images hide caption

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President Obama has called on small, elite military units to carry out several risky operations in the past year, like the hostage rescue this week in Somalia. Here, Navy SEALs are shown during a training exercise at the John C. Stennis Space Center in Mississippi. John Scorza/U.S. Navy hide caption

itoggle caption John Scorza/U.S. Navy

The U.S. military wants Afghan troops to begin taking the lead role in combat operations. Here, Afghan cadets who are joining the army are shown at their graduation ceremony on Dec. 18 in the northern city of Mazar-i-Sharif. Qais Usyan/AFP/Getty Images hide caption

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A student paints the Facebook logo on a mural commemorating Egypt's revolution last spring. The team from the CIA's Open Source Center monitors social media activity overseas. Manoocher Deghati/AP hide caption

itoggle caption Manoocher Deghati/AP