There are some important wrinkles in there though, such as the externalities of pollution. Imagine two countries on each side of a river, identical except one of them can make Product X more-cheaply because it allows toxic waste to be dumped into the shared river.

Less-tangible--but even more morally-fraught--might be the case where one country's competitive advantage comes from chattel slavery.

Specialization may confer advantage, but not all advantage is specialization.