James, there is another fear. The fear of what we'll become if we kill them all. It's powerful - the thing that comes to mind is the line in Pulp Fiction where Samuel Jackson explains to Tim Roth why he's giving him his money:
Jules: Wanna know what I'm buyin' Ringo?
Jules: Your life. I'm givin' you that money so I don't hafta kill your ass.
I'm willing to spend a lot to buy the lives of the Muslim world.
To paraphrase Spider Robinson, genocide gets your soul all icky.