I'm sure that Midwesterners are super polite to other white people, but it was definitely not my experience there as a minority.

I was born in the US but my ethnicity is visually ambiguous and people assume I'm Mexican, Filipino, or Indian (in that order) based on the type of brown person they grew up with. In CA, no one particularly cares what type of brown person I am. But when I lived in Ohio, I was told that I should "go back home where [I] came from", that I'm one of the good ones and should bring more of my family over, or that I'm "stealing jobs from honest Americans," based on whether the redneck in question thought I was Mexican, Filipino, or Indian. My cousin and his wife, in Indiana, used to experience the same harassment regularly until they started wearing their scrubs everywhere so people would know that they're doctors.

I turned down a very well-paying job in Ohio (and came back to CA) because the people there were so vile.