Trump feeds the mob and the mob feeds Trump. He followed up his racist tweets with another rally, in North Carolina, where the crowd showered him with calls of “Send her back! Send her back!” For anyone horrified by where such hate-mongering may lead, by what such a crowd might be capable of, I’m afraid that there is no natural limit. Demagogues don’t find radicals to lead; they radicalize their followers one outrage at a time. Trump drags his supporters down by association every time they fail to disown him, to condemn him. Eventually they have no one else — and no one else will have them.