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