Richard Johnson's comment about progressives in Europe criticising Americans for being racist seems equivalent to Atlanta lecturing those of us in New Hampshire about snow removal. Look how little snow they have on the streets! All clean, completely under control!
When they have snow, they don't handle it well. So also, European countries where everyone looks like second-cousins are now having difficulties with immigrants.
It's not very different when it's one American region criticising another. Vermont (or, ahem, New Hampshire) looks at Mississippi with disdain. Mississippians, black, white,and whatever, have a harder job. If I had to join a mixed expedition to colonise Mars, I might join the Mississippi contingent.
Update: Correction in the comments