Most Trump supporters, as far as I can tell, have one overriding desire - to be better than the guy next to them.
So mocking the disabled guy next to them? Makes them feel like they are better than that guy.
Grabbing women by the pussy and getting away with it? Makes them feel more powerful than the woman next to them.
Mexicans are rapists? Blacks get roughed up - and are from "shithole countries?" Makes them feel like they are superior to those types.
Waiters, bartenders and hotel clerks? Treat them like shit, thus demonstrating how much better you are than them.
Golf? Cheat as much as you can, because then you are (on paper) better than the people you are playing with.
Something proves you wrong? Take a Sharpie and fix it, so that you are right and the guy next to you is wrong.
Two courses of action to take? Take the one that "owns the libs" because then you are superior to them. Even if it hurts you - as long as it hurts them more.
Successful trans women? Mock them and take them down a peg, to make yourself feel a bit more superior.
That's what makes them happy - and that's what makes them want to emulate Trump. Trump is the very embodiment of the effort to be superior to the people around him.
There was a recent debate about the term "liberal." And the classic definition of liberal would apply to most people on this forum, even if the more recent definition of "liberal" is "a democrat." That's misleading because (for example) the rights to personally own property and guns are very liberal rights.
However, with Trump there is a clear delineation. Trump is anti-liberal in the classic sense. A classic liberal's definition of "better" when it comes to politics is something that makes everyone (or almost everyone) in the country better. Maybe it's the right to free speech, or the right to own guns, or a nationwide road system, or an EPA that prevents factories from polluting so much and harming Americans. But for Trumpies, "better" means "better than the guy next to me." And you can get there by improving your situation - or making his worse. Both ways the Trump supporter "wins."