That is how the capital account balances the current account for any nation where the nation with a current account deficit is structurally unable to run a trade surplus, especially the USA. That is the mechanism Varoufakis describes in The Global Minotaur. But it is not necessary for either trade partner to run a deficit if they can both balance their current accounts. They could just trade raw materials for manufactured goods. But FDI by one side is a capital account activity and it too can be repaid in raw materials and/or agricultural goods. Raw materials could also be traded for capital goods so that the country receiving FDI could add value to its exports. The requirement is that Current Account = Capital Account for both countries, by accounting identity. Else, what am I missing?

"It is not necessary to have hope in order to persevere."