Why do you think fanatical trump supporters such as the_donald are the way they are?

This depends on how you define “the way they are”.

One part is the standard cult of personality thing, where anything Trump says is true, and, if facts contradict this, then too bad for the facts.

Another part is spiteful thinking. Namely, I really despise group X, and if something is making group X mad, that means it goes against their goals, and that means it accomplishes mine. This is actually a sensible strategy if you think group X is smarter than you, by the way, but this is also how you can meme yourself into going against a volcano prediction program because that makes tree-loving libtards mad, which actually happened.

Third is something I call huffing semantics. You know how internet Republicans like @mr-cappadocia and @explainguncontrolandsafespaces (or whatever that guy’s name is) keep insisting that welfare is slavery? Because Democrats are the party of slavery because they were during the Solid South days, and therefore everything they do is pro-slavery? Incidentally, they all deny that parties switched. Why do they do this? It’s completely counterfactual and makes no sense.

That’s because they value semantics over substance. The identifier “Democrats” is more important. That’s also how you see people calling a group hypocrites - they say X but also not X! (cf.: Americans are such hypocrites, they voted for Donald Trump but also Hillary Clinton at the same time) This also makes these people naturally become attracted to “ironic” thinking. Namely: group X says they are against racism, but here we have this example of somebody being racist! Ahhha! How ironic. Therefore, group Y, which is where I am, is /really/ the one who is against​ racism, unlike the racist group X.

There are other factors in play, like the speed at which information propagates over the internet and the way it keeps circulating forever even if false. But I think it’s primarily these three.