Adam Smith argued nations should make whatever they're best at, full stop

In 'The Wealth of Nations', Adam Smith argued a country should specialize in making whatever it can produce more efficiently than anyone else, and trade for the rest, rather than trying to make everything itself. This idea of absolute advantage was the first systematic case against mercantilist self-sufficiency. David Ricardo later showed countries can still gain from trade even without any absolute advantage at all, but Smith's version came first and set the debate in motion.

— Adam Smith, An Inquiry into the Nature and Causes of the Wealth of Nations — 1776
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