"They’re in the remote possibility of building intelligent machines that act, and even appear, as humans. If this is achieved, eventually intelligent weapons of mass destruction will be built, without doubt."

Worrying about this strikes me as a bit daft when you can already convince actual humans to be your weapons delivery system.

It also shows some significant shortsightedness regarding scaling laws which an AI researcher ought to have more experience with. A more legitimate worry would be basement-grade Predator drones. Grenade-bearing quadcopters which use computer vision to track and target dense crowds are something which technology can do now, rather than something which might optimistically happen in a few hundred years.