See North Korea for a contemporary example of a country that produces everything internally.

Taking north Korea as an example is not a good idea. Also they still import allot through backallies. I don't see anything good from north Koreas way of doing things unless we want to go back 200 years

It’s an example of a country with constant shortages of basic goods including food.

The amount of global trade in the middle ages was enormous, literally from Europe to china with the middle east in between. If anything the laissez faire spirit of global trade was more alive in the middle ages.

Global trade has exploded since we adopted the shipping container and it's been just the latest thing in a long list of conventions.

I highly doubt that even per capita medieval folks were trading more than today.

this is a very silly comparison, why not compare to the vikings then, or cavemen, how did they get their iPhones?

That's the point, they didn't. You won't get your iPhone without globalized trade.

There was very far-reaching trade since the beginning of time. It just had to be carried by people and animals, and accordingly you only find small precious things traded far around the continents.

I just read 'The dawn of everything' and it seems that knowledge about the past has been evolving quite a bit in the past few decades. Societies still cling to the old myths of progress and premeditated development from hunter-gatherers in small bands over cities to kingdoms to states, but this a) not based on facts and never was at all (the ones putting out these ideas basically invented them over coffee) and b) not what happened.

The way the common narrative is accepted now can really hold us back.

I've been meaning to read that. How does it compare to Capital?

I've been meaning to read that - so no information yet, sorry.