Jeb Bush was left grasping for a response when a student challenged him during a meeting by declaring: "Your brother created Isis". Mr Bush, the former governor of Florida and sibling of George W. Bush, was wrapping up a town-hall style discussion when Ivy Ziedrich, a 19-year-old student at the University of Nevada, commanded his attention by asking him to take a student question. Her question revolved around a claim he made earlier in the meeting that America's retreat from the Middle East under the Obama administration was in part responsible for the rapid rise of the Isis terror group....