Here’s what I wrote following that appearance: “Mr. Greenspan’s performance yesterday, in his first official testimony since he let the genie out of the bottle, was a profile in cowardice. Again and again he was offered the opportunity to say something that would help rein in runaway tax-cutting; each time he evaded the question, often replying by reading from his own previous testimony. He declared once again that he was speaking only for himself, thus granting himself leeway to pronounce on subjects far afield of his role as Federal Reserve chairman. But when pressed on the crucial question of whether the huge tax cuts that now seem inevitable are too large, he said it was inappropriate for him to comment on particular proposals.

“In short, Mr. Greenspan defined the rules of the game in a way that allows him to intervene as he likes in the political debate, but to retreat behind the veil of his office whenever anyone tries to hold him accountable for the results of those interventions.”

I received an irate phone call from Mr. Greenspan after that article, in which he demanded to know what he had said that was wrong. In his book, he claims that Robert Rubin, the former Treasury secretary, was stumped by that question. That’s hard to believe, because I certainly wasn’t: Mr. Greenspan’s argument for tax cuts was contorted and in places self-contradictory, not to mention based on budget projections that everyone knew, even then, were wildly overoptimistic.

If anyone had doubts about Mr. Greenspan’s determination not to inconvenience the Bush administration, those doubts were resolved two years later, when the administration proposed another round of tax cuts, even though the budget was now deep in deficit. And guess what? The former high priest of fiscal responsibility did not object.

And in 2004 he expressed support for making the Bush tax cuts permanent — remember, these are the tax cuts he now says he didn’t endorse — and argued that the budget should be balanced with cuts in entitlement spending, including Social Security benefits, instead. Of course, back in 2001 he specifically assured Congress that cutting taxes would not threaten Social Security.

In retrospect, Mr. Greenspan’s moral collapse in 2001 was a portent. It foreshadowed the way many people in the foreign policy community would put their critical faculties on hold and support the invasion of Iraq, despite ample evidence that it was a really bad idea.

And like enthusiastic war supporters who have started describing themselves as war critics now that the Iraq venture has gone wrong, Mr. Greenspan has started portraying himself as a critic of administration fiscal irresponsibility now that President Bush has become deeply unpopular and Democrats control Congress.