This assumes that the us has an unlimited ability to monetize its debt. If this is not true than there could be a hard landing for federal borrowing. This was briefly tested in the 1970s when the carter administration issued debt in foreign currency.

The fed could find itself in the position of fighting a structural imbalance such that for every dollar lent to the government the deficit increases by 1.X dollars. This would be the case under rampant corruption, rampant inflation, or an economy collapsing.