The day that citizens can come afoul of the justice system simply by thinking certain thoughts is a day to be feared by everyone. There are certainly some people with terrible views that have no place in society, but it is far more dangerous to declare these opinions illegal than to allow freedom of opinion.
I don't think this would make any sense and would go against everything that the US constitution represents. Having an opinion is the right of every human being. Opinions stir debate and open grounds for discussing important political,social and economic issues. Without opinions there is no advancement in humanity or thought.
Humans have the right to express their own opinions without the threat of violence. Opinions shouldn't be illegal, no matter how distasteful they may be. Hate speech is banned in Europe because of Adolf HItler's regime 70 years ago. However, freedom of expression is the right of all beings so we can decide for ourselves what is right and wrong.
We're all human. We all dont think the same. So why the heck are you asking a question when it is not controllable? Sure, you can ban people from saying opinions but you cant keep them from thinking them. And, if opinions were illegal, there wouldnt be anything to have an opinion about. For example, lets say that I said that UNC is better than Duke. If opinions were illegal, that would mean that nobody could argue with me. BUT, it would also mean that I wouldnt have been legally allowed to say that, because I said my opinion. In fact, without opinions, this website wouldnt exist! Did you think about that? I think not. So no, opinions should not be illegal.