The key difference between "now" and "1940s" is that manufacturers are now much more specialized, dependent upon automation and fixturing, and less vertically-integrated. We don't just have row upon row of lathes and mills being run by competent machinists.
A modern automotive assembly plant typically does the following things:
- Stamp body panels
- Weld sheetmetal parts together
- Apply paint
- Bolt on a bunch of parts that came from outside suppliers
On the periphery of those plants are some operations like engine block casting, but in many cases nowadays those castings aren't even machined in-house.
Most automotive companies are logistics firms - they route a huge number of parts from suppliers around the worlds, and make sure those parts hit the assembly line at the right place and time. Each of the suppliers for those components is highly specialized at building those components. You've got brakes coming from a plant that does nothing but brakes, steering columns coming from plants that builds only steering column, seats coming from plants that just make seats. This is what modern capitalism has created - a lot of extreme specialization in pursuit of maximum efficiency. That's good for profits in normal times, but not necessarily the resource you want to lean on to do something in a crisis.
Much of the tooling that makes these parts isn't even made in the US anymore. So let's say you've got a plastic molding machine that normally makes glovebox lids and you want to convert it to turn out ventilator front panels. You need new tooling to do that, and that tooling often comes from S. Korea or China since we decided long ago that it costs too much to pay Americans to babysit an EDM machine. The same is true if you want to cast a magnesium ventilator frame on the machine that normally makes magnesium steering columns, or stamp out a steel ventilator mounting bracket on a press that normal punches out window regulators. By the time this tooling is turned around and takes a long boat ride across the Pacific, the crisis might be over.
Now, there are still places where you can find flexibility, but they are several "tiers" down the supply chain. Finding those sources and effectively managing their skills and talents will require some serious effort, and I'd be looking not at the automotive OEMs but rather some of the Tier 1 suppliers as a source of that management ability.
It'll be interesting to see who in the federal government knows this and how they direct their efforts. Wilber Ross (the Commerce Secretary) used to be a big swingin' dick in the auto parts world, but I have no idea how "in touch" he is with the industry nowadays.
