Discovering the Limit

At the end of 2008, as the economy collapsed and the pace of net Treasury debt increases quintupled, it seemed we were about to discover that limit. I presumed we had a little time for expansionary fiscal policy to boost the economy -- a year, maybe 18 months -- before the bond-market vigilantes would arrive. They would demand higher interest rates on Treasury bonds, which would begin seriously crowding out the benefits of fiscal stimulus. The U.S. government would have to react, pivoting from fighting joblessness, via deficit spending, to reassuring the bond market via long-run tax increases and spending cuts to Medicare and Medicaid.

But it didn't happen in 2009. It didn't happen in 2010. And it isn't happening in 2011. There are no signs from asset prices that the market is betting heavily that it will happen in 2012. Looking at the yield curve, it appears the market intends to swallow every single bond that the Treasury will issue in the foreseeable future -- and at high prices. The prices of inflation-protected bonds suggest that the market expects the new Treasury issues to be devoured without any acceleration in inflation.

Keynes Disciple

Although I worked for three years in the Clinton Treasury Department, and am a card-carrying member of the economist guild, I predicted none of this. Like most of my peers, I was wrong. Yet the most interesting thing is that I could have -- should have -- been right. I had read economist John Hicks; I just didn't quite believe him.

Hicks, one of the clever young Brits dotting i's and crossing t's in the writings of John Maynard Keynes in the 1930s, was responsible for the workhorse formulation of Keynesian economics -- the IS-LM model -- that has been the bane of many an intermediate macroeconomics student. It was his version of the IS-LM model that formalized and elevated a key insight: that interest rates paid by creditworthy governments would remain low after a financial crisis. This formulation holds even in the face of enormous budget deficits that greatly expand the supply of government bonds.

A financial crisis initiates a sudden flight to safety among bondholders -- widening interest-rate spreads, diminishing the private sector's desire to sell bonds to raise capital and encouraging individuals to save more and consume less as they, too, hunker down. Thus bond prices rise, and interest rates drop. As rates fall, firms see that they can get capital on attractive terms and so issue more bonds; households see the low interest rate earned on their savings and lose some of their desire to save. The market heads toward equilibrium.

Safeguarding Wealth

But something else happens on the path to equilibrium. The decline in interest rates and the rise in savings are accompanied by an increased desire among businesses and households to safeguard more of their wealth in cash. As a result, the speed with which cash turns over in the economy, the velocity of money, falls. And as the velocity of money falls, total spending falls, workers are fired, and their savings evaporate with their incomes.

Thus the equilibrium turns negative, with high unemployment and low capacity utilization.

In responding to a small financial disruption, the Federal Reserve can inject more money into the economy by buying bonds for cash, increasing the amount of cash so that even at the lower velocity of money we retain the same volume of spending. This eases the decline in interest rates, spending, employment and production into a decline in interest rates alone.