Much from American cultural heritage comes from America’s Christian past. It is Christian Civilization that is civil; not pagan, not Jewish, not Buddhist nor what have you.
Jesus teaches civility because He wants us to build a Christian Civilization, much unlike the one He walked in.
If the gang of obamabots gets its way, American civility will be gone in short order.
I believe there is a time and place for expressing anger and the use of profanity can help articulate that. In other words, it helps to get their attention.