Do you think Trump believes he's not racist?
Yes.
I think the biggest blockage to understanding your (er, the general 'your', not you personally!) prejudice is the concept of "If it's true, espousing that viewpoint isn't racist". It's one of the things at the centre of "he tells it how it is" praise.
Of course, the problem with that is when 'it'
isn't true (or, often, when there's a lot more nuance to it that the prejudiced person is unaware of or ignoring), but the person fervently believes it. At that point anyone who points out
accusations of prejudice is 'ignorant', or 'burying their head in the sand', or 'overly PC', or 'deluded'.
And so you become "One of the few people unafraid to tell the truth" in your mind, you're the person standing up against the oppression, you're the persecuted. It becomes an idea that 'racism' is '
choosing to be nasty against people who are different', but you're not
choosing to do it, you're coming to a perfectly reasonable conclusion based on an (erroneous) collection of facts. "That's not racism! That's just common sense!". Which in turn is why the
accusation of racism is so objectionable to them, because as far as they're concerned they're being perfectly reasonable and logical,
you just don't see that because you're prejudiced.
Catch-22. I've no idea where we as a society start to unravel this.