If censorship is hard to pull over there, why are cursewords forbidden on tv? Or nudity?
If you dress up like nazi, you won't be imprisoned in most of europe. Germany went a bit far, but they had their reasons :). If you dress as KKK, what will happen in usa? Can you guarantee you will be free to spread "white power" statements? I kind of doubt it. You pepper sprayed students just sitting in park peacefully protesting.
Personally I don't see why hatespeech should be legal, since I don't see how that is limiting our freedom of speech in any meaningful way? What is so great to have absolute freedom of speech, when making it absolute just legalises lying and you are free to character assasinate anybody. And his ability to fight is none, if he does not have the resources. And then, when company does it, you get Foxnews. And then you have 50% of population beliving creationism.