President Obama has turned to Congress to save him from staggering political isolation on the global stage. It is an isolation that is the inverse of the promise of a passionate and reciprocal multilateral embrace that carried him into office. Asking Republicans to rescue him from a foreign policy catastrophe entirely of his own making is not a neat political trick. It dramatically cheapens the office of commander-in-chief. Contrary to the President’s devious portrayal, therefore, the coming vote is so much more than a response to “this attack” or “the massacre” in Syria. The President had the audacity to ask...