What you fail to acknowledge is that by going against someone over any disagrement you're hurting not only civility, but you transform yourself into the very thing you're fighting against.
Hell no! Fight them back with better ideas, respect, and equality. But first of all, you have to understand what you're up against, study what they say, find cracks in their logic, and show that you're both on the same side. It's all a matter of perspective.
You respect them and then they lynch you. When a tolerant culture meets untolerant culture, the former usually backs off even if it's more advanced. Take France as example.
I think we should not be tolerant to people who violate basic human rights. They either behave or we should find a way to catapult them away.
Why does religion go against us, but we should not go against it? They take pride in hurting whatever I consider worthy.