> any public cluster would be outdated in 2 years

The private companies buying hundreds of billions of dollars of GPUs aren't writing them off in 2 years. They won't be cutting edge for long. But that's not the point--they'll still be available.

> Nvidia's profit margins on the H100 are crazy

I don't see how the current practice of giving a researcher a grant so they can rent time on a Google cluster that runs H100s is more efficient. It's just a question of capex or opex. As a state, the U.S. has a structual advantage in the former.

> far better ways to spend $1b in research dollars

One assumes the U.S. government wouldn't be paying list price. In any case, the purpose isn't purely research ROI. Like the heavy presses, it's in making a prohibitively-expensive capital asset generally available.

What about dollar cost averaging your purchases of GPUs? So that you're always buying a bit of the newest stuff every year rather than just a single fixed investment in hardware that will become outdated? Say 100 million a year every year for 20 years instead of 2 billion in a single year?