Imagine scale economies were not only external to firms, but were also

Imagine scale economies were not only external to firms, but were also external to individual countries.

That is, the larger the worldwide industry (regardless of where firms or plants are located), the cheaper would be the per-unit cost of production. Describe what world trade would look like in this case.

ANSWER

Presumably each country would specialize in some component of the final product. This would result in in a high volume of intra-industry trade.