As a white kid hated by the Hispanic majority in New Mexico I thought I understood prejudice. Then I befriended black people in Los Angeles. I think it's fair to say that I'm aware of some minor percentage of it but I sure don't know it. I mean, just this morning I was explaining that Trump's tax cuts were basically written for me. Yeah there have been times I couldn't get a coffee 'cuz I was too gringo but there have also been times the cops have said "sorry for pulling you over, sir, we thought you were hispanic." Actively malicious or passively malicious is the wrong focus. Your mention of the Weimar Republic and LGBTs is right, I think. If I'm looking for an "honest debate" about whether a group of people should be treated as fellow humans, what I'm really looking for is a forum in which I can assert they aren't human. And if I can assert it convincingly enough, they aren't. "Teach the controversy" is shorthand for "we're wrong but also loud and aggressive."