I think that when you take a political stance, be it left, right or centre, you do so because you have a viewpoint of what is best for your town, country, world, etc. Having done this you will become aware of people with the opposite point of view. People who want to stop or prevent your idea of good. That seems to be a pretty good reason to get angry.In my long observation of political news, I have often wondered:
Why do conservatives/right wingers seem SO ANGRY?
I tried googling that question once hoping for articles that explored that maybe interviewed people or something, but oddly got the reverse, articles which pondered why left/liberals were "so angry"