actually, if you listen to white supremacists, it's clear that even they don't actually believe in it anymore.
the original nazis were all about how superior they were. they wanted to wipe out or enslave all of the other races, to make room for themselves. and, remember: they weren't even white supremacists- they were strictly german nationalists. the french were franks, but they had a real hate on for russians and the british, too. they even thought the poles (who live right next to them and in fact probably founded berlin) were subhuman. they were bellicose, arrogant and certain in their delusions - they were superior, and all others would be defeated by their superior intelligence and superior tactics. naturally.
today, white nationalists are all about protecting the fragility of their endangered race and their threatened culture. they talk of a "white genocide" on the bottom end of an inferiority complex. listening to them talk, it's weird to even call them supremacists at all.
of course, the truth is that they don't understand history: this white race that they've imagined never actually existed. white people probably came from central asia and intermixed with all kinds of indigenous people as they migrated into europe. in the historical period, europe has seen large scale levels of immigration from the middle east and from asia and more recently from africa. the closest thing you're gone to find to a pure white person is probably somebody off the finnish bottleneck, but even they speak an uralic language.
so, you can't even define what they're claiming is superior. what's ever come out of ukraine?
but, if you forget about that, how do you want to do this? if white people are superior, how can they be being exterminated in a genocide? now, ignoring that you can't define white, you have to find a way to define superior. well, if superiority is determined through natural selection, a white genocide suggests white people are not superior. if it's over brawn, it still doesn't work; and, if it's over brain, white people are getting outsmarted, too.
so, what these so-called white supremacists really have is an inferiority complex and a fear of not holding up. what they want is a safe space where they can breed without being polluted, because they know they're too weak to dominate the people around them - like putting a critically endangered species that can't adapt into a wildlife enclosure in a zoo.
it's the reality of it.