Which relies upon them not being damaged in a collapse and having the skilled technicians to run them, the inputs necessary to operate them, the supporting infrastructure and a whole host of other things. Just as society is complex, so too is the machinery we use to sustain it and that's why we have dedicated training programs for such, because you can't run a nuclear power plant or even solar farms based solely off reading a book from a library.
Yes, our economy and infrastructure is very complex.
We aren't looking at a zombie horror movie where ~95% of the population just up and dies over a few weeks/months. A societal collapse doesn't just 'happen,' and then everyone important to infrastructure is dead all at once.
You are basically supposing that suddenly, magically,
all the essential parts of making our nation work all disappear at once.
My point, is that barring all-out nuclear war, no situation that even comes
close to that will happen.
Okay, so the economy collapses, there's rioting and looting in the major cities, and not the carefully-protected stuff right now, but mass riots that kill thousands and burn entire districts down. Government officials are killed, the cops either die, join riots, or GTFO. The military is out of the picture either out of principled refusal to get involved in civilian political strife, or because they're stuck fighting China on the far side of the world.
Okay then, what all is really lost? Not anywhere near as much as some people think; 99%+ of the population is still alive, including 99%+ of all the critical infrastructure labor.
Let's assume things are much,
much worse. The riots cause fires that go completely out of control, hysterical clashing between heavily-armed Antifa thugs and regular citizens erupt throughout the major cities, and
hundreds of thousands die. This would be the worst sort of civil unrest the West has
ever seen.
You
still have 99%+ of the population alive. Even if some major port facilities and railroads are damaged, you aren't losing
all of them, and even if somehow we can no longer get imported raw materials from overseas, very nearly every raw material in the world can be produced right here in the USA. Some of it requires reactivating mines that couldn't compete with super-cheap stuff from China or the third world, and some very specific things we'd have to either find new sources of or develop substitutes for.
That's okay, we've done that before. Before WWII something like 95% of rubber was sourced from specific raw materials in SE Asia; after the war, during which the Japanese had choked off control of it, the majority of rubber was now made through synthetic processes that had practically not existed before then. More recently, back in ~2010 China controlled something like 95% of Rare Earths production, at one point they tried to use that near-monopoly to establish a stranglehold on the market. Within 2 years other extraction sources had been spun up and China no longer had the ability to choke things out.
Some things are easier to deal with, some are much harder (cutting-edge semi-conductor production, the majority of which runs out of Taiwan right now, being one of the most difficult), but you wouldn't just need a societal breakdown to
permanently spike production, you'd need to commit genocide and outright nuke infrastructure to do so.
Society can still not only recover, it can
easily recover. It would be a great tragedy, but my point about 'all it takes is
one group of well-skilled people with a good 3D printer and a lathe' is
just how ridiculously thoroughly you have to destroy society for it not to be able to recover.
A lot of damage can be done, and a lot of people can suffer and die in very painful and tragic ways, and the ability to recover will still easily exist. The fact that a lot of easily-accessible oil deposits and coal seams have been mostly-extracted as you said isn't
remotely enough to keep society from recovering from painful and harsh blows. (And to answer as to what oil resources are still easily-accessible with simpler technology, the tar sands in Alberta and Saudi Arabia's primary oil fields just off the top of my head)
So, what kind of 'societal collapse' is it you're talking about? A giant meteor striking the Earth? The Yellowstone supervolcano erupting and rendering a third of North America uninhabitable?
