How much of what goes into our weapons is made elsewhere, or mined/refined elsewhere?
We have seen this problem during oil booms, in that there are just not enough people who know how to do the job out there. While that is a great deal for those of us who do know how to do things (that's when we make our money), it isn't the way to spool up an industrial base that will require more precision than ever.
During WWII, factories were converted to wartime production. Sewing machine and typewriter manufacturers were making firearms. Others converted from building cars to tanks, and so forth, but the raw labor and facilities were there for the most part, people who could do the work, and run the machinery needed, or had been idle for only a decade or so because of the depression.
Mining stepped up, but the miners and mines were there. Some reopened after the depression, others expanded. Now they have been reclaimed, flooded, or laid idle for decades, and other minerals are barely located, especially some critical for electronic systems. Now, it is cheaper to buy from elsewhere, partly because the enviros will delay everything every chance they get.
Even on an emergency war footing now, I think the amount of sabotage from people who think they are 'saving the planet' would be as bad as enemy agents ever mustered then.
While I think the first stage would involve making the tooling and robots to manufacture the materiel needed, and that America could conceivably rise to the occasion given time, we would not have the warmup phase that lend-lease gave us in WWII, either. Eventually, I believe we could surpass that level of productivity (without H1Bs and illegal aliens), but it would take a little while to spool up, across the board.
