Barack Obama (the son of a white / European / Caucasian whatever) mother and an African father would have been denied a seat at a Woolworth's lunch counter in the 1950's. It's the prejudiced supremacists who deny anyone they don't consider pure a seat at the table. When Obama did run for president, he faced racist tropes from Trump and his supporters ("Obummer").

If white supremacists want to maintain their numerical advantage, they should stick to marrying their cousins (the white ones) and have lots of inbred babies like their ancestors did.