For two years, President Obama has boasted that he accomplished what his predecessor had not. “I ended the war in Iraq,” he has told audience after audience. But a resurgence by Islamic militants in western Iraq has reminded the world that the war is anything but over. What Mr. Obama ended was the United States military presence in Iraq, but the fighting did not stop when the last troops left in 2011; it simply stopped being a daily concern for most Americans. While attention shifted elsewhere, the war raged on and has now escalated to its most violent phase since the depths of the occupation. The turn of events in a country that once dominated the American agenda underscores the approach of a president determined […]