Sounds logical to me. It's already remarkable that we haven't done this with fission weapons. It's not unreasonable to assume that within a century we'll have antimatter weapons. Destructive potential only goes up.

We could not come close to destroying the world with fission weapons. We might make things very hard for humanity, but the world and life would continue, perhaps even benefit.

Every year the IQ needed to destroy the world drops by 1 point.