An unmanned U.S. Predator drone flies over Kandahar Air Field in Afghanistan in 2010. Apple has rejected an app that tracks U.S. drone strikes around the world. Kirsty Wigglesworth/AP hide caption

itoggle caption Kirsty Wigglesworth/AP

John Walker Lindh was captured in Afghanistan in 2002 after fighting with the Taliban. File Photo/AP hide caption

itoggle caption File Photo/AP

A boy watches a group of Afghan and U.S. commandos in their up armored Humvee in Shindand Afghanistan. The special forces have become more prominent in the U.S. war effort. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

A training session for instructors who teach hand-to-hand combat, or combatives, at the Fort Benning military base in Georgia. Pouya Dianat for NPR hide caption

itoggle caption Pouya Dianat for NPR

Spc. Ben Purvis (center) helps train Afghan troops on how to use mortars in the eastern province of Kunar in June. The top U.S. commander in Afghanistan, Gen. John Allen, points to several factors in the rise of "insider attacks" on American forces. He says relations between U.S. and Afghan troops are good overall. Lucas Jackson/Reuters/Landov hide caption

itoggle caption Lucas Jackson/Reuters/Landov

This image provided by IntelCenter on Dec. 8, 2010, shows a frame grab from a video released by the Taliban containing footage of a man believed to be Sgt. Bowe Bergdahl. The 26-year-old Army sergeant was captured by the Taliban more than three years ago. AP hide caption

itoggle caption AP

Gen. Norton Schwartz (shown here in October 2010) is stepping down as the top U.S. Air Force officer. Tim Sloan/AFP/Getty Images hide caption

itoggle caption Tim Sloan/AFP/Getty Images