U.S. Attorney General Eric Holder holds a news conference Wednesday in Kabul. Holder was in the Afghan capital to talk to officials about improving the justice system and fighting corruption. Ahmad Massoud/AP hide caption

itoggle caption Ahmad Massoud/AP

U.S. Marines take cover as they are involved in a gun battle in March during a patrol in Marjah, Afghanistan. In February, U.S.-led troops set out to rid the area of insurgents and set up a viable local government. But Taliban militants have returned to the area. Dusan Vranic/AP hide caption

itoggle caption Dusan Vranic/AP

Afghan national police and U.S. soldiers on a joint patrol in a neighborhood on the outskirts of Kandahar city. The U.S. strategy in Afghanistan depends on training and equipping the Afghan security forces, making them self-reliant and allowing U.S. troops to withdraw. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR