The topic remains the subject of ongoing research. Puzzle 2: Can the United States borrow without increasing its debt? The second puzzle has emerged more recently: Why does it seem that the United States can borrow without a corresponding increase in its debt? As is well known, the United States has been running large current account deficits for many years.
Financing these deficits has required substantial borrowing from abroad. However, the net increase in U.S. liabilities has been quite small relative to the cumulated current account deficits.