The US funds (and used to even moreso) scientific endeavors that stand to bolster the entire country all the time. Medical research is the obvious one, DARPA is the defense based one (though oftentimes defense is just a post-hoc justification for a lot of those), the Department of Agriculture is constantly researching improvements to the farming industry, the Bureau of Weights and Measures and the NSA fund cryptography research.

Research and development of new technologies often is a "rising tides lifts all ships"-type deal, which it is absolutely in the government's best interest to support.

For China, the best case scenario would of course be to control a locked-down best-in-class frontier model that the rest of the world becomes reliant on. The US seems to be beating them at that, and "Everyone is reliant on the United States" is a pretty bad scenario. A middle ground, positive outcome is that no one is reliant on locked-down closed models, so they're supporting that outcome.

It's really not that nefarious.

"public" doesn't mean "love and kindness with no self-interest".

We only think "government spending is for hippies" in the US, and only when we don't look at public spending like defense bills.

Of course it's in self interest. It's too bad that the US has gone the other direction and cut public funding for research.