Point of order, in the US, religious belief/creed is a protected class. You can't fire someone for being Jewish, for example. On the other hand, certain belief

Point of order, in the US, religious belief/creed is a protected class. You can't fire someone for being Jewish, for example. On the other hand, certain beliefs of certain religions would be potentially incompatible with workplace discrimination law, including law that protects other protected classes. So it gets a little murky. One thing you can say is that if you have a religious belief that isn't causing you to bother other people, that's protected in the U.S. You are correct about political beliefs, though. At least as far as I can find, political affiliation is not protected. But even if it were, this would necessarily not cover all possible political beliefs, for the same murkiness reasons as above.