Great historical account, and a real hat tip to capitalism lol. Even warlords, Or Especially Warlords, want consumer goods and will not bite the hand that feeds that desire it seems.
Of course there will be trade after any big collapse in society, it may take a little bit to get established but it always comes. With our one it wont be just bags of grain and beaten copper trinkets either, it will all the scavengings of 100+ years of industrialization. People can be very innovative especially when they are pulled out of the fields and have a lot of free time, or in our case, pulled off their desks and away from their mice. They have the time to think and to create, all manner of goods and services.
Say SHTF.
What consumer goods are even going to be available?
Is Wal-Mart still going to be open? Their trucks still running while the rest of the country is experiencing the SHTF? Restocking their shelves everyday? Accepting CC/EBT cards while the rest of the system is down? Or would it be ransacked of everything, maybe even burnt down?
Starbucks? Are they still going to be importing their crap tasting coffee beans from over seas?
McDonalds?
While in Afghanistan, I studied/monitored more than a few warlords. We call them warlords, they call themselves Tribal leaders. For they were responsible for safety and security of their tribe. That meant the basics, food, water, shelter, security. Not a Acme hot dog and bun toaster oven.
They still engaged in trade as rudimentary as it was compare to our JIT/BAU system. But that trade system is what a few to several years
post-SHTF would look like here in the US. Fuel in Afghanistan was not a sure thing (not uncommon for fuel trucks to get stolen, it was a big business), just like electricity. No fuel, they did not go far both from a practical stand point, and a security one.
Have to get through the bottleneck.
After that, some semblance of society/civilization/trade will emerge.
What will that look like . . .