Honestly I think they know but don't care about all that because they felt gaslighted by the media and other politicians. Trumps rise is a failure of the media and the politicians. These people spend time watching news stories about dangerous Mexicans, dangerous black people, dangerous Arabs and then they're told by the politicians that none of that is happening or its not that bad.
These people think they're going crazy until Trump shows up and says "i see it too! You're not crazy, this country is falling apart!" To them he's the one person who seems to be watching as much TV as they do and who agrees with the hysteria the news tries to sow. That's literally all he had to do to win the support of millions. Just say "america is dangerous just like the news shows us!"
I think they voted for him as revolt to what America is becoming which is much more liberal and a place where minorities and people who live alternative lifestyles can come and thrive.
It's all fun and games when those Black folks are cooking their food, sweeping their floors or being their nanny, or when those Hispanics are landscaping their property or working on some construction, or those homosexuals are fighting for equal rights, but as soon as the aforementioned start working their way into positions of being CEOs, business owners, managers, supervisors, and the highest reaches of government like state reps and state senators, vice president, and president were you hardly see any minorities there is a problem.
Those are supposed to be the jobs reserved for lily White folks, and Trump came in at just the right time dog whistling on their fears of people that are not like them.
It's a changing world and those cacs are going to fight it tooth and nail, but a day is coming where they are going to be the minority and a lot of them feel people that are not like them are going to take their position and mistreat them like they have done others for so long. That's the real elephant in the room for a lot of White people.