Not really.

I am a rhetorician by education and experience. Rhetoricians have been studying persuasion and motivation and epistemology for a while now. As Aristotle said. rhetoric is the antistrophos of dialectic.

These people are not brainwashed in the conventional sense of the word. The giveaway is the fact that the party (and its ideology) morphed. It was not the people changing to meet the party and its ideology, it was the party changing to meet the desires of the people.

The trajectory is clear, even if the mechanism is complex and not necessarily one sided (nothing is ever that simple when it comes to human behavior). Not going to go into that now for reasons of time and space--maybe I will write about it in my blog (blatant plug there).

Trump was the guy who "said what everyone was thinking." Seemingly without fear and with NFG. That is why he is perceived as strong and why they eagerly leap to his defense (despite his many sins).

Like called to like, even if the like didn't initially strongly identify.

You then get a mutually reinforcing cycle centered on shared identity and belief that is only reinforced by outside "persecution."

These people believe either because they already believed ITFP or because it became a necessary part of their identity. They WANT to believe.