Earlier this week, Roger L. Simon of PJ Media broke a story with shocking revelations, contending that slain U.S. ambassador Chris Stevens was in Benghazi on September 11 to buy back Stinger missiles from al-Qaeda groups that had been originally provided to them by the U.S. State Department. Simon cited two former U.S. diplomats: Stevens’ mission in Benghazi, they will say, was to buy back Stinger missiles from al-Qaeda groups issued to them by the State Department, not by the CIA. Such a mission would usually be a CIA effort, but the intelligence agency had opposed the idea because of...