Ever since the Arab Spring began videos have been making the rounds of massacres in Syria and Bahrain, photos of violent protests in Egypt, excited tweets, bloodied faces, Molotov cocktails and all the rest of the revolutionary chatter. It is tempting to side with the people battling tanks, even when you don’t know why they are battling them. That was how Americans ended up cheering an alliance between the anti-American leftist Kifaya movement and the Muslim Brotherhood in Cairo against the Egyptian government. Or backing an Al-Qaeda linked Islamist group against Gaddafi in Libya. America was built on revolution and...