Many Americans seem to think other nations are NPCs in a video game that only exist to make the main character — the US of A — feel good. They conveniently forget that other nations have their own national interests that are often at odds with ours.

This line of thinking might have worked in 1950 or 1990 when the US had the leverage over others, but we don't live in that world anymore. And it's up to us to get used to the new world instead of making bad decisions based on the one we grew up in.

This contradiction "we have to make an agreement with China for mutual slowdown" but also "we have to ensure we will always stay ahead of China" would work. Its just fantasy. The only way to enforce this is with military force and the cost would be too unbearable. You could try trade restrictions but the previous tariffs did not work and doubt future ones will to. US citizens (and thus politicians) won't bear that pain. Thus at a minimum this contradiction will mean AI will continue to develop until both US and China are at the same level. Playing with logic gives you possible scenarios. If China catches up within 1 year then negotiations could begin. If China takes many years to catch up, say 6 months behind now, then next year 5 months behind, then year after 4 months behind then expect overall AI development to proceed at full speed. The one way you could do it is to negotiate to transfer direct technology to China that will ensure that they will have the capability to be on par with USA. Politicians won't do this publicly as they want to get elected but they could make a deal that appears to appeal to both sides while actually transferring technology.

This is the part I find being left surprisingly hand-wavey.

If you extrapolate it out, you see that it has a high likelihood of inciting physical force (read: military action) as a means of enforcement, so perhaps that's why nobody promoting ideals has been direct about it.

Some people would like to have law that protects them but doesn't bind and for others to be bound but not protected.

They would like to slow down China while speeding ahead. Why wouldn't they want that?

Now they have to make that happen somehow.

Probably thinks he has a better chance negotiating with China now than with misaligned AGI in the future.

Sure, Dario needs to decide first if he sees China as an enemy orva friend.

Limiting NVIDIA chips already turned China into silicon compete mode, and China is already far ahead in robotics.