By Martin Wolf

"I regret to say that the Federal Reserve independence is not set in stone. FOMC discretion is granted by statute and can be withdrawn by statute." Alan Greenspan, The Age of Turbulence.

To critics it is now the "Bernanke put" – the belief that, as under Alan Greenspan, the US Federal Reserve will always ride to the rescue of Wall Street. The jubilant response of traders to the Fed’s 50 basis point cut in the short-term interest rate might justify this suspicion. But saving Wall Street from its follies is not the Fed’s objective. It is an (unfortunate) by-product of the attempt to do its job.

It would be wonderful if those responsible for this most absurd of financial crises could be punished without damaging millions of innocent bystanders. But it is impossible. If the Fed does its job, it helps the financial sector. The latter will, no doubt, recover and then find some new, imaginative and currently unforeseen way to generate a possibly bigger crisis several years hence. Whereupon, it will expect the Fed to do its job, as Wall Street sees it: saving the economy, by saving finance. Moral hazard matters, but only for the poor.

Yet will the Fed always be able to oblige? The answer is not so clear. The resolution of each crisis lays the seeds of the next. Thus, the easing by the Fed after the east Asian and Russian crises of 1997 and 1998 contributed to the subsequent stock market bubble. The dramatic easing after its bursting in 2000 contributed to the recent housing boom. The disruption in money markets brought about by the end of that boom has led to last week’s sharp cut in rates. The question, then, is what this will lead to.

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