There’s such a thing as minimal unit of production. For some processes. Very important, we are surrounded by cheap space-age materials all involving those minimal units quite big somewhere in the chain.

That’s also why humanity can’t just get rid of oil, everything around us is made from oil products. Everyone, including off the grid indie artists, relies on materials as good as magic made from oil products.

World economy of today pretty fundamentally can’t work as a set of autarkies.

However, in the 70s, when autarkies were still considered by everyone (the Cold War and possible future Cold Wars and the remaining colonial friction), making them was studied a lot. Including what you can and what you can’t do with autarky.

The complexity and efficiency of production will have to be reduced by orders of magnitude if that happens.

TBH, I like stuff made then. Good engineering and all. But say goodbye to computers capable of running AAA games, to the Web as it exists, to being able to buy so many things, to the general consumerism of today. You’ll again have to know how radio works to use a radio, how computers work to use a computer, and how magnet tape works to use storage media, and a lot of that to not break things you use daily. And they’ll be expensive as hell.

The point - not just “America”. But, again, somewhere in the 70s “America” could claim that it’s probably the most self-reliant country in the world. Except it’d quickly stop being that without markets for stuff produced.

Whatever happens, happens.