Personally speaking, I stopped sharing opinions around these topics once I saw people losing their livelihoods for carrying the "wrong" opinions. I'll still discuss with close friends and family. My sister and I have some very spirited conversations around politics, but I wouldn't do the same with my boss. I don't even know what my boss's opinions are and I'm fine with that. As for the "American" comment, there are countries where physical altercations happen in Parliament over political disagreements. Holding passionate opinions is definitely not unique to Americans.