Why be violent?

Why do people keep killing in protest for abortion? It makes no sense! To kill one person's life to save another is just stupid. As of right now it is the pro-life people doing most of the killing but that is only because abortion is legal. If abortion was illegal then we would see a bunch of pro-choice people killing pro-life people.
But the pro-life people doing the killing are doing it in the name of God and calls them Christians, but if you are willing to kill other people you are not a true Christian. It's just like when "Christian" do violent acts on gays. They give real Christians a bad name.
People really need to change their violent acts and try to make a peaceful conclusion then the fight in abortion. I don't care how pro-choice someone is i would never hurt them, I would be happy to engaged them in a heated, but friendly, debate on abortion and would try to come to a reasonable agreement but most people would not do that, they would get so heated that they would end up yelling at each other.
So if the abortion issues has any chance to be fix we need to stop hating on each other and try to find an agreement that makes both sides happy.