His thesis involves at least two ideas (1) projects which could exponentially increase our AI capability are just around the corner (will happen by the end of this year or some time next year at the latest) (2) it's possible for state actors to deter those projects with sabotage (he coins the term Mutually Assured AI Malfunction).
It doesn't make sense to me however because the cost of the next AI breakthrough just doesn't sound comparable to the cost of creating nuclear weapons. With nuclear weapons you need this extremely expensive and time consuming process, and you need to invest in training these extremely skilled people. With AI, the way everyone seems to talk about it, it sounds like some random undergraduate is going to come along and cause a massive breakthrough. We've already seen Deepseek come along and do just as well as the best American companies for practically pennies on the dollar.