Even more fundamentally, we should be able to teach students that imports, not exports, are the purpose of trade. That is, what a country gains from trade is the ability to import what it wants. Exports are not an objective in and of themselves: the need to export is a burden that the country must bear because its import suppliers are crass enough to demand payment.
Damn. I\’ve been known to make this point often enough myself. But I was sadly deluded enough to think that I was being vaguely original in doing so.