An Afghan police officer stands guard at the border crossing with Pakistan on Saturday east of Kabul. Violence in Afghanistan fell in 2012, but insider killings by uniformed Afghans against their foreign allies rose dramatically. (Associated Press)

An Afghan police officer stands guard at the border crossing with Pakistan on Saturday east of Kabul. Violence in Afghanistan fell in 2012, but insider killings by uniformed Afghans against their foreign allies rose dramatically. (Associated Press)