“Patriotism is the last refuge of a scoundrel,” Samuel Johnson said. A few centuries later his fellow Englishman, Winston Churchill, quipped, “The United States invariably does the right thing, after having exhausted every other alternative.” It’s not true of the United States, but it is true of Barack Obama who, having exhausted every alternative that involved appeasement or pretending that ISIS wasn’t a threat, has decided to do the right thing. As long as he gets enough applause for doing it. With his approval ratings, particularly on American leadership and national security, lower than Assad’s, he decided to exploit September...