They can praise it as long as it does not cross the line into hate speech. You see all types of videos, forums, books, and whatever else you can think of praising racism. The only reason you don't see more people praising it is because they know it would effect them a personal level because not every shares thoses fews or want to be around people that do.
I think it is dishonest not of share that belief with people if you hold it because people should be able to choose if they want to continue to associated with you. You may find people that share your views, don't care, or stop talking to you but at least you are honest.