According to a story in Sunday’s Washington Post, as President Obama and his advisers measured their response to the mass killing in Libya, they were mindful of the fact that diplomats in Tripoli had told them, in the words of one official, that “certain kinds of messaging from the American government could endanger the security of American citizens.” “Overruling that kind of advice would be a very difficult and dangerous thing to do,” said Ben Rhodes, the deputy national security adviser for strategic communications. “That was the debate, and frankly we erred on the side of caution, for certain, and...