The Challenge of Deterring ISIS

Through its coalition against ISIS, the West and its local allies are struggling to save a region now teetering on the edge of a geopolitical precipice. The amalgam of coalition forces—much of it still notional— is an engineer’s nightmare: composed of countless moving parts of marginal quality, with American pressure and a fear of ISIS as its only lubricants. The U.S.-led force also confronts an unpalatable reality: the adversary is undeterrable.