In our current economy, that reversion would be even more painful. In the short term, as much as I hate the US military, their "freedom of navigation" guarantees are essential. In the long term, every nation/bloc should make sure it has the materials to re-bootstrap if necessary.
Here in Korea, we just had to scramble because Japan decided to limit photoresist and high-purity HF exports. I count the scramble as a good thing for national self-sufficiency.
My apologies for going way off topic.
For fans of that podcast, it's one of the best single episodes. Dan Carlin has a particular style, which is not for everyone, but fans know what to expect.
That's why it pains me when I see activists crying for correcting the wrongs at all costs, "justice" at the cost of "order". It's ultimately a self-destructive approach that's akin to cutting off the branch you're sitting on, after first setting it on fire.
The biggest threats to the current order are companies and politicians that refuse to address our unsustainable level of pollution, which is pushing our climate out of balance.
They're the people advocating for a "starve the beast" approach to governance, literally trying to create a financial crisis just to get a few percent taxes shaved off their bottom line (and probably think they can profit off the crisis too).
They're the people pushing for increased gerrymanding and census manipulation, which radicalizes politics on both ends of the political spectrum, shuts out people in the middle, and erodes faith in our institutions on the long term.
These things are by far the biggest threat to the long term stability of the current order in the US.
The knowledge, How to rebuild the world from scratch
We can't do a Saturn V today. We might be able to do a Saturn V equivalent, though, as both NASA and SpaceX are retracing the steps towards heavy lifters.
“Imagine waking up the next morning and the world totally forgot all knowledge on Linux Kernel, and you are now tasked to release the next major version with major changes / improvements”
And remember the documentation and tests we have on Saturn V is certainly not as great as what we have on Linux kernel.
They're having to analyse the garments in medical scanners to work out how the fabrics work.
The idea that technology that enabled the equivalent of the space race could be lost within a century is quite sobering.
I first need to finish and ask someone to proofread my long overdue post on my views about advertising industry.
With no readily-accessible source of energy, we would never be able to reboot. And everything readily-available has already been mined. We now drill deep below the ocean surface for oil.
The Ecotechnic Future, The Retro Future, The Long Decent, Not the Future we ordered - all great books on what will happen if these systems crumble from resource depletion.
As much as I want disagree with his views, they look more sound every day. He is actually doing a follow up series on these topics on his blog (Ecosophia) currently.
Consider also the amount of people needed all across the industries and supply chains of any product you know. I don't have hard sources, but I fondly remember this essay by Charles Stross. TL;DR: how many people does it take to maintain (not improve) current technology level of our civilization? Charlie puts it at 100 million to 1 billion.
And now think of the economies and infrastructure needed to just feed these people. We hit 1 billion around 1804, which is far in the industrialization process, and most of these people weren't working to support the technology levels anyway.
For some insights, I recommend tracking down and watching Connections. It's an old show, from the era where TV shows actually made sense, and it drives home just how much our current technology is dependent on right combinations of social, economical and technological conditions.
EDIT: fixed site reference in .
 - http://www.antipope.org/charlie/blog-static/2010/07/insuffic...
 - https://en.wikipedia.org/wiki/World_population_milestones
 - https://en.wikipedia.org/wiki/Connections_(TV_series); I hear you can find it on a site that starts with "daily", and ends with "motion.com".