Why, in such a debt-heavy era, is inflation still such a Bad Thing(TM)?

Question

Going through the Wikipedia article on inflation, a number of pros and cons to inflation are covered. Most of the "cons" of inflation (cost-push inflation, hoarding, hyperinflation, diminished allocative efficiency, etc.), don't become a problem until inflation is well above the levels currently targeted by The Fed.

A number of "pros" are also covered, but one I don't see addressed anywhere I've looked is this: the average U.S. household debt is 3x the average annual income. Our government is also in debt to the tune of \$21T, which comes at a cost of \$400B per year in interest paid. I do see acknowledgement that higher inflation eases debt, but nothing on why increased debt hasn't incentivized us to increase inflation.

Wouldn't a higher inflation rate be a good thing? It would devalue those (household and federal) debts, making them easier to pay off, and saving the interest paid for other budget items. If the Government (and most Americans) were running closer to the black, I can see why you'd want to keep interest low, but given the unprecedented situation, why not allow inflation to float higher?

Answer 1

While many points can be made about the pros and cons of inflation, the following is one of the most fundamental.

Suppose A borrows \$100 from B and inflation is 5% per year. To keep things simple, assume the terms of the loan require repayment after one year. When the repayment falls due, A pays B \$100, but because of the inflation it is only worth (at the original price level) $100/1.05 \approx \$95.2$. So A's debt has been somewhat eased by the inflation (and if the term of the loan were much longer the easing could be much greater). But what about B? In real terms B has lost the same amount that A has gained.

Other things being equal, therefore, inflation benefits borrowers and costs lenders. And in total, amounts lent must equal amounts borrowed. It may be that the the borrowers (government, struggling households) are more visible than the lenders (better-off households, foreigners). Nevertheless, the effects on lenders, and on incentives for future lenders, cannot be ignored. Where inflation is expected, lenders will as suggested in Henry's comment demand a higher interest rate to offset their expected loss on the principal repayment.