Terror suspect al-Awlaki was killed in a 2011 drone strike . The U.S. said he was top operative for Memo in U.S. . Government sought to keep memo secret , saying release would harm national security . al Qaeda said that force authorization against al Qaeda in general applied to Anwar al-Awlaki .
Terror suspect Anwar al-Awlaki was killed in a 2011 drone strike . The U.S. said he was top operative for al Qaeda in Yemen . Government sought to keep memo secret , saying release would harm national security . Memo said that force authorization against al Qaeda in general applied to al-Awlaki .