mild. The damage in financial markets was much greater than the decline in the broader economy, illustrating the distinction Greenspan had drawn in 1996 between an asset-price collapse and a genuinely systemic economic crisis.
The episode also revealed the central contradiction of Greenspan’ s approach. He was willing to identify the possibility of a bubble but deeply reluctant to use monetary policy to restrain it. In a 2002 review of the experience, Greenspan argued that bubbles were extremely difficult to identify conclusively before they burst. Raising rates enough to puncture one might also damage productive investment, employment and the broader economy. The central bank should therefore concentrate on containing the consequences after the collapse, rather than attempting to prevent the boom itself.
There was considerable logic in this position. A central bank cannot know the correct price of Microsoft, Amazon or the entire stock market. High valuations can reflect exaggerated enthusiasm, but they can also anticipate extraordinary future profits. And monetary policy is an extremely blunt instrument with which to correct a particular class of asset prices. Raising rates affects homeowners, manufacturers, small businesses and workers who may have no connection to the speculative excess. The Federal Reserve could easily cause a recession while trying to prevent one.
But the cleanup doctrine created its own incentives. Investors increasingly believed that the Federal Reserve would tolerate rising asset prices while responding forcefully to falling ones. The idea became known as the“ Greenspan put,” borrowing the language of an option contract that protects its owner against losses. Its reputation began with the Fed’ s response to the 1987 stock market crash and grew after rate cuts during the 1998 global financial turmoil associated with Russia’ s default and the near-collapse of Long-Term Capital Management. The Richmond Fed’ s history of the Greenspan put notes that the concept reflected a belief that monetary policy reacted asymmetrically to market movements.
The Federal Reserve did not literally guarantee stock prices, and Greenspan did not rescue every investor. Yet expectations matter. If market participants believe the central bank will ease aggressively after a crash but will not tighten comparably during a boom, risk-taking becomes more
A broker on the floor of the New York Stock Exchange watches stock prices drop on December 6, 1996. The loss was due largely to a statement made by US Federal Reserve Board Chairman Alan Greenspan, who described the inflated stock performance as“ irrational exuberance.”
attractive. Gains remain private while some of the broader consequences of losses may be cushioned through lower rates, emergency liquidity or other interventions. The policy designed to clean up bubbles can therefore contribute to the conditions in which the next bubble forms.
This issue became more consequential during the housing boom. After the technology collapse and the September 11 attacks, the Federal Reserve reduced rates sharply and kept them low. Cheap credit was not the sole cause of the housing bubble or the financial crisis, which also involved flawed regulation, securitization, leverage, government housing policy and extraordinary failures of private risk management. Nevertheless, Greenspan’ s confidence that markets could largely police themselves, combined with the cleanup philosophy, came to look much less convincing after 2008.
The phrase“ irrational exuberance” consequently survived the reputation of the man who coined it. Greenspan, who recently died at 100, was once celebrated as“ the Maestro”— the central banker who had helped guide the United States through low inflation and the long expansion of the 1990s. After the financial crisis, critics recast him as an architect of deregulation, easy money and excessive confidence in financial markets. Both portraits are too simple. He was neither an omniscient conductor nor the sole author of every subsequent disaster.
The broader significance of his speech lies in the question it could not answer. Central banks can influence asset prices, but they cannot reliably determine what those prices should be. Ignoring bubbles can allow leverage, malinvestment and fragile financial structures to accumulate. Attacking them can crush legitimate innovation and make unelected officials responsible for deciding which investments are socially acceptable. Cleaning up after them can prevent a recession from
JON LEVY / AFP via Getty Images
28 FINANCIAL HISTORY | Fall 2026 | www. MoAF. org