[A] Trumpian four years would almost certainly involve a significant degradation of the unwritten restraints on presidential conduct, an acceleration of royalist tendencies that may be built into our system but still deserve to be slowed down, and a blurring of reality-TV and political culture that takes us several leagues further along the road to President Camacho. I don’t think that the nebulous possibility of dealmaking should tempt liberals to welcome this kind of experiment; I don’t think the hope of a more working-class-friendly G.O.P. should tempt conservative reformers to learn to love it either. And the fact that recent...