The Democratic line on Donald Trump is beginning to sound - bear with me on this - a little like arguments made for continued government funding of public broadcasting. One the one hand, we’re told, public money makes up only a small part of the Public Broadcasting Service’s budget. On the other, cutting that allegedly small amount would do irreparable harm to American civilization. You understand what’s meant by these arguments, but you want to say, “Well, which is it?”

Hillary Clinton’s general-election campaign hasn’t begun in earnest, but I wonder if I’m wrong in seeing...