A lot of times, white people call things or people racist as a joke or a generic insult. For instance:

• In response to someone expressing a preference for white shoes over black shoes
• In response to someone saying something that offends them for some unrelated reason
• In response to expressing connection to a particular ethnicity
• In response to mentioning that white people are white and it matters

It’s not ok to do this because:

• Jokes like that work by assuming that calling someone or something racist is inherently absurd
• Which rests on the assumption that there is never a *real* need to call someone or something racist, because it rests on the assumption that real racism is over except for a few fringe groups with no power
• But racism is still a problem, and it still does tremendous harm to people of color

Using “racist” as a joke or generic insult sends the message that you refuse to acknowledge that racism is still a problem. It sends the message that you have contempt for people who point out racism. Don’t do that.