By legislative design? If a nuclear bomb could be made with hardware store finds the world would already be over. Big collaborative works raise the stakes and the observability for surveillance. Apply for a job at a defense supplier or even and energy company.

If AI production is limited to big labs and big data centers then it is de facto contained and monitored. If you know where all the ASML machines are then you know the reproduction rates of chips. If no one can buy or build the machines required to concentrate uranium or plutonium to critical levels then the threat is contained and monitored.

You can dig up all the Uraninite you want. It was never much of a secret that uranium had dark applications. The machines and processes where thankfully big and expensive enough that only the most focused bad actors could aquire them and then hold the world hostage to the degree they do. If al-qaeda or isis could have used $40 bombs from home depot instead of expensive planes they would have (and they do).

You have to legislate and control the big, expensive, and slow things. Dynamite and phentanyl are so dangerous because they move much more easily. Freedom does not have to be a suicide pact. If the inconvenience of requiring prescriptions or access to dynamite reduces harm then it is net positive?

In Plan C the government essentially misses the opportunity to implement the multinational deal while the threat of covert projects is still low (fewer latest-gen chips unaccounted by tracking measures, worse models/algorithms to use for RSI). That's why it says the probability of a deal is lower and lower each month rather than outright zero.