There was enough in the 9/11 hearings on Tuesday and Wednesday to make partisans on all sides unhappy. Partisans for the truth, however, have some ground for optimism.

If one were a Bill Clinton partisan, one would not be happy about the portrayal of the 42nd president and his anti-terror record. It appears that the Clinton administration had as many as four opportunities to try to kill Osama bin Laden in 1998-9, and seized upon none of them.

Sandy Berger, national security adviser during those years, testified on Wednesday that Clinton had ordered using"the full measure of the CIA's capabilities" to eliminate bin Laden...

...At the same time, if one were a George W. Bush partisan, one would not be pleased by the depiction of the 43rd president and his War on Terror record. In 2001, the Bush people inherited a holdover terrorism" czar," Richard Clarke, but they demoted him and cut his access and clout.

Did the Bush people lack confidence in his ability? Not really; after all, on the terrible day of 9/11, Condoleezza Rice, Clarke's boss, instructed Clarke to run the crisis-management operation in the White House Situation Room while she chose to hunker down in a secure bomb shelter...

...When they came into power, Bush & Co. had the idea that they needed a comprehensive review of national security policy, which called for less emphasis on terrorist networks, such as al-Qaida, and more emphasis on terrorist-sponsoring states, such as - in their minds, at least - Iraq.

That review took more than seven months; the first cabinet meeting on the administration's anti-terror policy took place on Sept. 4, 2001.

Do changes in policy, from one president to another, take time? Of course. But the Bush folks managed to reverse Clinton policies on taxes, global warming and abortion within weeks of taking office; it's obvious that unlimbering a new anti-terror policy was a second-tier priority for them...

...If an anti-terror czar is like a fireman, the Bush people left Clarke with the power to see what was happening but without the power to send out the fire engines. He had been worrying about al-Qaida for a decade, and yet even as he saw terror flames growing on the horizon, the Bush people pushed him aside.

No wonder Clarke is an angry man. In his memoir,"Against All Enemies," he recalls being in the Situation Room on 9/11 when he got a call from an FBI colleague:"We got the passenger manifests from the airlines. We recognize names, Dick. They're al-Qaida."

Clarke wondered, expletive-ly, how those killers had gotten on board."CIA forgot to tell us about them," came the FBI reply. In other words, his worst nightmare had come true: Al-Qaida operatives had slipped between the jurisdictional cracks of the federal government; the CIA had a list of al-Qaida names, but hadn't passed them on to the FBI, nor to airport security officials...

...What's striking about Clarke is not that he expressed his apologies to the 9/11 families for their loss, and for his own degree of responsibility for that loss. That was a bit of political theater that his fellow panelists must be kicking themselves for not having thought to do themselves.

No, what's striking about Clarke is that he delivered detailed testimony that bulls-eyed the incompetence of his ex-colleagues in the Bush administration. While all the other witnesses were generous in their praise for each other - leaving one hard-pressed to recall, as they spoke, that 3,000 people had died on their watch - Clarke was blunt. The Bush administration, in particular, had done a bad job, he said - and he said it under oath.

Of course the Bushies have a right to call Clarke's credibility into question. They can point to his smarmy letter of resignation, addressed to Bush, dated Jan. 20, 2003, in which Clarke praised Bush for his" courage, determination, calm, and leadership." But if the White House really wants to knock a hole in Clarke's chronicle, then top officials should joust with him on a level playing field - on which they, too, are under oath...

...The White House pleads"executive privilege," but that's a dodge. If the issue is important enough, constitutional nuance ought to give way to the people's right to know. In 1974, for example, the sitting president of the United States, Gerald Ford, testified, under oath, before the House of Representatives about his pardon of Richard Nixon. And ever since then, Ford has enjoyed a deserved reputation as a straight-talker...

...For the moment, the Clintonians and Bushites seem to be playing for narrow personal and political advantage.

By contrast, Clarke, warts and all, seems to be thinking about the truth - which means he is thinking about the national interest, as well as the long haul of history.

These hearings have the potential to embarrass all concerned. But while the truth might hurt top government officials, former as well as present, America will benefit from a full, if painful, account of mistakes that were made.

The 9/11 Commission is due to issue its final report on July 26; the 10 commissioners have an opportunity to help their country - if they can put aside their partisan differences and deal with the truth.