Easy to say now, but there's just not enough manpower to make _everything_ in house that we deem strategically important. And if the price isn't viable on the free market, how is it justifiable long term? I generally agree with your sentiment though.
Not enough manpower at the moment, for sure, but we should create it through education and social investment. It's generally a strategic advantage to have manufacturing capabilities no matter what discipline; it's less that we are reliant on China for this one particular thing and more that we have allowed our once-strong manufacturing muscle to atrophy. We subsidize gas heavily because it's a strategic advantage to the nation; call it a hunch but I think there are more knock-on benefits to being able to make stuff than is readily apparent (and I thought such a view would be more popular on Hacker News to be frank).
I think you are bang on with capabilities vs capacity. We should have one factory for anything critical so that in case we can’t get as much as we need on the free market we can ramp up capacity by building more of the machine that makes the product. If you don’t have all of the know how that is in that machine or plant design already in your one factory making the product you are starting from zero. Hence why all of China’s cheap labour deals had technology transfer riders.
