Comment by defen

These simple models of free trade work fine when discussing commodities or raw materials, but one thing I never see addressed (I'm far from an expert, just an interested layman) is that modern manufacturing involves far more than the raw inputs - there's complicated logistics and an entire holistic knowledge base of the company or companies which produce a thing. A society can forget how to make things, especially if no one in the society makes those things any more. The classic example is that "no individual knows how to make a #2 pencil from scratch". Or, more recently, the USA can't even produce large numbers of N95 masks. So, there can be a short-term benefit to free-trade, but an unknown cost down the line if your trade partner goes away for some reason and you can no longer make things you were trading for.