How much must the US trade balance improve to be sustainable?
Core argument: Setting the US net international investment position on a sustainable path requires a trade balance improvement of about 2% of GDP if the dollar's "exorbitant privilege" is maintained, implying a real effective exchange rate depreciation of some 15–20%.
The most persistent driver of US deficits is the attractiveness of US financial assets to foreign investors owing to the central role of the dollar in international transactions and to the perceived safety and creativity of US financial markets. The US net liability position is likely overstated, [but] the present level of the trade deficit is not likely to be sustainable, as it would push the net international investment position [NIIP] (as a ratio to GDP) beyond levels that have been sustained in any advanced economy. The tariff war may reduce the trade deficit by slowing US growth, depreciating the dollar, [but] puts at risk the ability of the United States to finance external debt at low cost [the “exorbitant privilege”], increasing the burden on future generations. Setting the NIIP on a sustainable path requires a substantial but not unprecedented increase in the US trade balance. If exorbitant privilege is maintained, the adjustment is some 2% of GDP, implying a depreciation in the real effective exchange rate of some 15 to 20%. Were the United States to lose its exorbitant privilege, the adjustment rises to over 3% of GDP, implying a larger depreciation and faster accumulation of debt for the same level of the trade balance.




