Official US national debt exceeds $21 trillion. National debt increases over $3 billion per day.
Another day older and $3 billion deeper in debt!
The U.S. government pays the interest by issuing new debt. But that new debt increases total debt and (eventually) drives up interest rates, which requires more borrowing to pay the annual interest payments. Another year older and deeper in debt! A reset will occur when the debt load becomes too heavy.