First, you're assuming you can reliably identify someone who is "genuinely racist", which I'm not inclined to believe.

Second, you assume that someone who is "genuinely racist" is so likely to engage in cruel behavior as a result that she should be punished preemptively, like the "future crimes" division in "Minority Report". Generally we only punish people for things that they've actually done, which I believe is a valuable restraint on our part.

Third, kicking these people out of their jobs, homes, classes or whatever might well reduce the amount of racist cruelty in the country. And forcibly resettling housing-project residents to reservations out in the hills would probably reduce crime (if you think that's a ridiculous example remember the Freakonomics claim that crime went down twenty years after Roe v. Wade because many criminals simply weren't born, so the idea that the removal of certain types of people from society would improve it already has currency). I don't think I have to explain why we don't do things like that.

Refusing to hire someone, or even firing someone, because you don't like his views is fine. It's your business. Make it Democrat-free if you like. However, public institutions, which many schools are, don't get to do that, and encouraging an employer to fire someone is still a mean thing to do. Especially over a thought-crime. Especially over a private conversation. Especially when you can't really be sure of a net benefit.

Maybe society would be better off, but one of the things that we don't do is hurt people who haven't *done* anything wrong for the betterment of society. See above.

And consensus on something like this is a very dangerous thing. It means that if I don't believe as the majority does I can be punished for it regardless of anything I *do*.