And so the scavengers will feast and the plagues will bloom again. And because no-one will agree, we will have little local wars over resources. Maybe someone will grab a warhead or two. Technology still keeps happening, so expect at least one plague to be targeted. And some group will have a "if we can't have it, nobody can," so a self-irradiated country will get to keep a resource out of some other group's hands. You'll get real genocides, then.
Nobody wants to participate in the one way of getting their hands bloody, pretending that they won't get bloody later on, up to the elbows.