Elissa Lerner: Since when do we authorize killing American citizens? The Obama Administration has approved a targeted killing, of radical cleric Anwar al-Awlaki, a spiritual leader to two of the 9/11 suspected hijackers, Maj. Nidal Hasan of the November Fort Hood shootings, and Umar Abdulmutallab, the would-be Detroit airplane bomber in December. Al-Awlaki, despite his current...