Oren Cass argues the thought of comparative benefit driving commerce is outdated. I conform to a sure extent, however he doesn’t clarify why. I’d say intra-industry commerce (IIT) – a staple of educational analysis because the Eighties – is one purpose, however that doesn’t present justification for defense. In truth, his ignorance of IIT suggests his case for protectionism is ill-founded.
How a lot intra-industry commerce is there? Some current estimates from Czarny, Elżbieta & Folfas, Pawel & Szarek-Piaskowska, Aleksandra. (2024). Intra-industry commerce: a portrait of worldwide patterns throughout 2000-2022.
Supply: Czarny et al. (2024).
The US share has gone down a bit since 2018, maybe resulting from export controls (though that’s conjecture on my half). Even then, IIT accounts for over 1 / 4 of complete US commerce.
See additionally Richard Baldwin‘s recounting of IIT over time.