I've thought for a while that applying the old Roman practice of damnatio memoriae would be the most appropriate way to deal with ISIS. How satisfying it would be for any "legacy" they hope to achieve to be wiped from the world's collective memory, so that nobody even remembers who they were in twenty years. All of their "martyrdom" and death would have resulted in a sum total of nothing. Not the most inspiring legacy for the disaffected youth of the future.

They've finally lost Fallujah, and have been taking heavy losses from the air during their retreat (see below). Mosul is next on the list.