An unmanned drone armed with Hellfire missiles is shown over southern Afghanistan. A Hellfire missile fired from a drone was used in 2011 to kill an American in Yemen who the Obama administration says was an al-Qaida leader. Another American died in that attack, and a 16-year-old American was killed in a separate drone strike. Lt. Col. Leslie Pratt/AP hide caption

itoggle caption Lt. Col. Leslie Pratt/AP