[SubiculumCode]

Yes and no. The U.S. can and does make new money to pay debts...basically out of thin air. As a self imposed limit, they agree to pay interest on that debt. Again, yes they can create money to pay that interest, which because of the mechanism they set up, would cost further interest payments.

So what's the real limit?

Inflation.

If you have too many dollars in circulation chasing too few goods, you get inflation.

Therefore, the limit is the the extent to which interest payments on the national debt are sufficient to induce inflation beyong productivity growth.

At least, this is my understanding.