That would be “culturist”, not “racist”.
Insist on the definition of actual racism (judging based on genetic, not behavioral, differences), and make the left defend the value of the “urban culture” in comparison to the distinct “American” culture of Western Civilization.
Actually, the correct term is “ethnocentric”
Unfortunately, these days ethnicity is being deliberately tied to race rather than culture, so “ethnocentristity” is percieved as racism. When it really isn’t.