It's called self defense. You may call it whatever you like. You need to go read that Book, you know the one, let me see, ah yes, I think it is called the Bible. Did you ever see where God ordered the children of Israel to utterly wipe out some of their enemies? (though not all of them) Self defense is not murder. If you would not defend your family from someone breaking into your house, with murder on their mind, then there is no sense talking to you at all. We are not talking rocket science here.