Here's a sociological law I've discovered over the years: "In any given nation, there will be one and only one socioeconomically-dominant group (which may be racial, ethnic, or religious in nature), and it is that dominant group that will be the most racist, and will commit the most egregious acts of racism."
This is true in every single nation on the planet. It also shows why, even though whites are not biologically predetermined to be more racist than anyone else, we are certainly the most racist in America. The same goes for the Han in China, the Brahmins in India, the Tutsi in Rwanda, and the Sunni Arabs in Saudi Arabia.
America is browning. By 2050, America will be majority-minority, meaning whites like thee and me will make up less than half the population. This doesn't bother me or you, but the prospect scares the crap out of a whole lot of whites out there. They see the multi-colored/cultural nature of the Democratic party and the increasingly monochromatic nature of the GOP, and they see the GOP as the last refuge of whiteness.
Of course few will say this out loud, but it's the underlying motivation.
In other words, Trump - and Trumpism - is the last gasp of white supremacy in America. This is demographically inevitable. Even if Trump's enablers are successful in winning a second term for him, America is browning. Once Trump's attempt at dictatorship-in-all-but-name is done, the GOP is done, minimized, and well on its way to political Whigdom. The only question is, how much damage will they do to America's political norms along the way.