If you have never done so, I suggest reading "The Authoritarian Dynamic".
It's a fascinating read, especially in context of Trump, Brexit, etc. The point is clear though....there is a subset of people that have authoritarian tendencies. It's not race driven either, but rather they value order and obedience above all else. But those tendencies, especially politically, don't impact their voting until they physically feel threatened. Whether that is economic threats (white working class in the Midwest for example), physical safety (threat of ISIS) or something else, if it threatens their perceived notion of order, they will naturally align to leaders who "stand up" to the threat. It's important to note that they aren't against something because they hate "insert minority group here". It's the threat of their existence. It could be anyone threatening them, they would reach the exact same way.
Here is one other interesting theory from the book...physical threats will turn people without authoritarian tendencies into authoritarians, so long as the threat remains. That is why R's do well in elections when these threats exist. It's why they are also so strong on "law and order". It activates that trigger in some people.
The scariest part about it all is that Trump's existence isn't what created the circus. He just was the one this group aligned to. There will be others just like him and, according to election results, many are likely to succeed.
But IMO, as a country, we need to stop calling people Nazi's, racists, bigots, etc. There are certainly people who are. But to those who aren't, the mere suggestion that someone who appears to be seeking order similar to what they desire is called a racist, will perpetuate the cycle of feeling threatened. I know that is unlikely. But the boogeyman of "cancel culture" keeps the "résistance" alive.