So, the town I live in got burned down by some Confederate guy back in the day. The people around here know who he is and haaaate him.
One of the teachers at the local uni (I've long since graduated, but I still live here) is from North Carolina, and in one of our classes, she said when she first moved here, she had no idea what a horrible murderous monster he was. Back where she was from, the guy was seen as a local folk hero. Her parents refused to believe her when she told 'em what was up. They couldn't understand how some dude that's been treated like a hero for over a century could be such a terrible dude.
A lot of people don't make the equation between the confederacy and how awful it was. To them, it's a part of their cultural identity, and they legitimately do not get why it was wrong. It's a part of them. It's always been a part of them. And they can't handle flipping that worldview on its head. Most folks can't. It's a shitty component of human nature.
Man, I've lived in the Midwest for my entire life, and the only folks I know who are super regressive are the rich fuckers. Worst racism I've seen was in the rich neighborhoods. One lady I was staying with was keeping an eye out on 'those Hispanics' because she couldn't tell if they were gardeners or folks who were up to no good. In the poorer/average places, where I've always lived, people ain't like that. It's classism more than racism. People like to paint stereotypes of dumb poor folks, but that's just classism too.
Sounds like you're from California. Maybe don't paint the Heartland with such a broad brush?