I vote for #3.
We waged total war on Germany and Japan, but we never had a policy of trying to kill all Germans and Japanese. We fought their governments, and when they were destroyed the war was over.
This war is a lot more difficult, as there is no government to target. But I don't think I'll ever be ready for total war that has the killing of over 1B people as its objective. There's no question we have the ability to do it. I'm just not sure that I want to support or remain a part of the society that would do such a thing.