He's cancelling the tour probably because of death threats. Like serious death threats. Think about the joke. It's not just about hating Trump, its about the precedent that we can think positively about the idea of murdering a public figure if we don't happen to like that public figure. Well, celebs are public figures too. So he's probably worried about the boomerang effect at this point. Of course that is not justified in any sense, but that is probably the reality of the bottom feeder level of political disagreement in our society at this point. How much lethal violence is fashionable?