They have already beheaded people, drowned people, raped and stoned women, killed children, crucified people. You cannot deal with them like a “normal” enemy. Either we fight to win at all costs or we lose.
Well - so far that is “their people”. Just like the world turned its head in Cambodia, the Congo, and all the other hell-holes with civil war, etc. (I have mentioned this to my kids when they study the Holocaust “so it can never happen again”. It KEEPS happening kids! It is happening NOW!)
You make a good point though. But the goal needs to be to exterminate them as the nukes probably won’t deter them. And I think it would be a hard sell to nuke some/all of their command centers. And I’m not so sure how effective that would be either.