“The government” isn’t a person. It can’t know things. It’s a complex, chaotic system of various people with competing interests who know things at different times and have power over different things.

Which is why we elect leaders of government who have more power to direct the internal machinations of government than we do directly.

Also, based on our leadership (and the likely reelection of that leadership) and how many Americans are refusing to follow basic sensible health guidance, this pandemic is going to go on for at least another year, maybe multiple years. It makes sense to start now if the payout is 6 months later.

Amortization on these facilities is not 6 months. It's years, likely a decade or more. There's only two companies in the whole world with the expertise to make these machines. And the machines have a high failure rate. Every nation on the planet is demanding more capacity. Do you believe that the very tiny number of people who are capable of expanding production capacity are just sitting on their laurels? This is categorically different than building something like a tank where most of the parts can be built in any machine shop.

You have to assume that every country on the planet, not just the US, has the same problem you're ascribing to the US. That they could just order new production capacity into existence, but they are choosing not to.