That's a helluva question. I think that some people are just more susceptible to some kind of hardcore ideology. I don't think that it's a function of intelligence, either. One of my closest friends, a very intelligent guy, is down the orange rabbit hole.i'm on a slightly different internal monalogue. i've been wondering why i , we, are not susceptible. perhaps it is subliminal stuff on channels i do not watch?
I've done a lot of reading on the subconscious. When you combine a basic (normal) bias with repetition and increasing isolation, your subconscious can be trained to believe some pretty insane things. To your point, you kind of create your own subliminal conditions.
This particular one is a weird blend of three sociological currents: Political, religious and cultural (cult). It's a lifestyle. And it's somehow grabbed, what, about 25% to 30% of the country. The rest are those who just sell their soul to politics and go along for the ride.