Although we still do not know the answer to the original mystery, the case provided a look at the methodical way that Mr Cheney, Mr Libby, Karl Rove and others in the Bush inner circle set out to discredit Ms Wilson's husband, Joseph Wilson IV...

What we still do not know is whether a government official used Ms Wilson's name despite knowing that she worked undercover. That is a serious offence, which could have put her and all those who had worked with her in danger. We also do not understand why the federal prosecutor, Patrick Fitzgerald, chose to wage war with the news media in assembling his case, going so far as to jail a Times reporter, Judith Miller, for refusing to reveal the name of a confidential source.

The potential damage from that decision remains of real concern. But it was still a breath of fresh air to see someone in this administration, which specialises in secrecy, prevarication and evading blame, finally called to account.

The fall of this skilled and long-respected public servant is particularly sobering because it arose from a Washington scandal remarkable for its lack of substance. It was propelled not by actual wrongdoing, but by inflated and frequently false claims, and by the aggressive and occasionally reckless response of senior Bush administration officials - culminating in Mr Libby's perjury.

The inherently political trial of I. Lewis "Scooter" Libby, the former chief of staff for Vice President Dick Cheney, was bereft of an underlying crime, subject to the whims of an arrogant and overzealous prosecutor in the person of Patrick Fitzgerald, and totally beside the point once Deputy Secretary of State Richard Armitage was revealed as the "outer," so-called, of Valerie Plame...

Perjury is a serious matter, and its importance is minimized at the risk of undermining the integrity of the judicial process, which depends on fact-finding and truth-telling.

And here the matter ends - in the eyes of the law, and for the purposes of this trial. Even Mr Fitzgerald, driven as he is by overweening ambition, now calls the case "inactive" and does not expect to file further charges (unless the prospect of further media attention changes his mind). The tormentors of the Bush administration calling for an expanded investigation deserve nothing but scorn. Their target is the destruction of an administration and a war policy they loathe. Justice is not their aim.

They must now take their case to the another court - the court of public opinion. Even with an unpopular administration conducting an unpopular war, their prospects are dim.

There is little here for either critics or supporters of the Bush administration to sink their teeth into. Did Bush and his aides completely trump up the case for war and then set out to discredit anyone who called them on it? Did they instead allow themselves to be convinced too easily by evidence that tended to show them what they wanted to see? Or was the president acting reasonably on information that appeared solid at the time? Many people wanted those questions to be the subject of the Libby trial, but they weren't, and nothing revealed in the trial puts them to rest.

The case has been compared to the prosecution of Martha Stewart for lying to investigators who couldn't make the underlying charges of insider trading stick. But there is a difference. The lifestyle-guru industry was not known for holding itself above the law. The Bush administration, on the other hand, repeatedly claimed for itself the power to determine its own bounds, whether in the prosecution of alleged terrorists, the use of wiretaps or the definition of torture. It may be less than satisfying to see the law finally catch up to the administration in the form of perjury convictions against the vice president's ex-chief of staff. For now, though, it will have to do.