As Bruce Bartlett correct observes:
Although it is thought that inflation is an effective way of
reducing the burden of debt, this is no longer true. For one thing, a
declining portion of the debt is financed with long-term securities.
Today, just 3% of the debt consists of bonds with maturities of 20
years or more; 10 years ago, the proportion was four times greater. To
the extent that the debt consists of short-term securities that must
constantly be rolled over, inflation does nothing to erode its value
because interest rates just rise to compensate, raising interest
payments and borrowing, thus maintaining the real value of the debt.