I’m not sure what the financial deal is on these planes. I spent thirty plus years in the military industrial complex. Items that only the US buys are super expensive. That’s because the US doesn’t buy enough of them and on a long enough term that companies can invest in automation. So, stuff only sold here is essentially hand built by top quality craftsmen. When the US stops buying, even briefly, the workers get laid off. The plant may close, and whatever they have that’s being taxed for its original purchase value gets sold off, or given away, or scrapped. That means that if Uncle Sam wants more of whatever, they have to find someone to produce it because the original company is either gone or isn’t in that business anymore. The highly trained employees moved away or opened a vape shop. You won’t get them back.
If Uncle Sam wants production capacity that production capacity must be used all the time...every month of every year until Uncle Sam doesn’t want it anymore. Hence, for whatever deal the government makes, it makes it having in mind that if it doesn’t said item most likely won’t be available. Oh, and the more we sell, the more companies automate, the cheaper the item gets.
While the military industrial complex is rightly criticized from a moral perspective, it’s not likely to be reined in anytime soon until the economic incentives you speak of are addressed. I’m not sure that there’s an easy solution, but perhaps our government should start by insisting that large military companies be diversified, with plans to convert their defense production to other purposes during down-times.