Before they gather in Cleveland for their convention, it’s not too soon for Republicans to begin thinking about what exactly a Donald Trump defeat might be like.

As with his now-documented habit of charitable promises that seldom materialize, Mr. Trump never intended to endanger a sizable part of his personal wealth to fund a presidential campaign. That means he’ll continue to campaign on the cheap, by saying incendiary things and having them transmitted by the free media. Expect more speeches like the protectionist-cum-conspiracy...