It is hard not to feel protective over Donald Trump while the political classes are seething and scornful. They are unacquainted with such powerlessness. Control was never supposed to stray this far from their grasp. And their rage, manifested in every hapless attack on Trump and his supporters, actually seems to be improving the likelihood of that outcome they fear most of all. How tempting, under these circumstances, to rush to his defense, as so many in the conservative movement have already done. The Donald has boldly made himself a standard bearer of unpopular (…within the political bubble), yet critical...