If getting angry revealed that your ideas and your doctrines were correct, we couldn't wade through all the "correct" people.
It's happened to me. You start to talk about something from the Bible, and suddenly a contorted face comes into view along with a screaming voice, condemning not only your ideas, but you. Never bring up some subjects to certain people while they have a potentially deadly weapon in their hands!
First of all, I see these people as coming from congregations where you are not allowed to disagree with or even question Bible doctrines or church practices.
Let's see now, I believe that in secular governments, that is called totalitarianism. Pardon me folks, but are you a member of a totalitarian church? Such ideas are considered an abomination in government, but are tolerated in religion.
Secondly, I see the Angry Christian as one who is insecure in his belief. "If only my preacher was here, he'd show you!"
When we are not allowed to ask questions, something is very, very wrong.
So, how did I get to be so non-argumentative? No one can make me angry about my faith. After all when a boat builder has worked on his craft for years, he should not be afraid to take it out on the water.