"White" is a relatively modern concept, and one that can be quite nebulous. I see some people call Bernie Sanders white, but I also see white nationalists who dont consider Jews white. Back when the British were committing a genocicde against the Irish and driving millions of Catholic refugees into a predominantly Protestant America they weren't considered white. Some Nazis considered Japanese people "honorary whites". People around the Mediterranean are a whole mixed bag- Italians, Greeks, and Spaniards have all been treated as white or non-white at times. Racists still debate whether Cleopatra and other Coptic Egyptians should count as "white" or not.

And of course Europeans have been making up divisions and killing each other over it for centuries. The very concepts of "Italy" and "France" and "Germany" and "Spain" and the like are pnky a few generations old.

It's not just "white" people though. The Japanese have a history of committing atrocities against their neighbors in Korea and China. Chinese history is largely the story of the Han people conquering the nations around them, and they are still committing genocide against groups like the Uyghurs and Tibetans today. Sudan had the genocide of the Darfuri in the early 2000's. The Rohingya genocide in Myanmar is still ongoing. We could go on and on.

The idea that only "white" people are racist is, itself, a racist idea.