I think that us-vs-them mindset you're describing is not a distinctive feature of religion, but really of a human nature. Anywhere people are organizing in grou

I think that us-vs-them mindset you're describing is not a distinctive feature of religion, but really of a human nature. Anywhere people are organizing in groups us-vs-them mindset can form. It doesn't matter, if it's a football team, a chees club, a business, a nation or just a group of music fans... It can literally appear anywhere. Organized religion is no exception.