If he knows what he's doing, and he doesn't, that would be even worse. That would mean he is deliberately attacking the very fabric of your democratic society. I am confident that in 20 years from now Trump will go down in history as the biggest mistake the US have ever made.
When it comes to stroking peoples emotions, he knows how to do it, that's what I'm saying. To rile up his base he knows exactly what to say. To enrage the other side, he knows exactly what to say and how to say it (and when to say it). The guy is a master at redirection. Mind you, this NOT a defense of him or what he says, rather, one must acknowledge his ability to start up a debate.
His next tweet could be about anything, but you can guarantee two things: The base will line up in support and the other side will take heavy aim. It's clockwork.