In his TV interviews this week following the release of his new book, former CIA chief George Tenet reveals a deeply troubling account of his agency’s assessment in early 2003 that Saddam Hussein indeed was stockpiling weapons of mass destruction.

It was that assessment, and of course, the regrettable speech based on it by then Secretary of State Colin Powell to the United Nations Security Council, that became the decisive public justification for President Bush to launch the worst foreign policy fiasco in the history of the United States, the invasion of Iraq.

How does a head of the world’s most powerful intelligence gathering agency explain, after all, that its determination that the U.S. and its allies were in imminent danger of attack from weapons of mass destruction was flat wrong?

First of all, it is yet another pathetic lie coming out of the White House now that, well, after all, the “whole world believed there were weapons there.” That is simply not true. There were U.N. inspections teams under the direction of Hans Blix scouring the nation of Iraq during the same lead up to the invasion, and they’d found absolutely nothing. Many on the U.N. Security Council remained skeptical after Powell’s “smoke and mirrors” presentation, as well.

Still, Tenet cannot be let off the hook now, even if he’s howling that Bush has tried to make him the “fall guy” for the whole Iraq fiasco. His predicament is akin to Scooter Libby’s. Yes, the administration chooses to exercise damage control by pinning the rap for its crimes on a single figure, and that’s not fair. But it doesn’t mean that either Tenet or Libby were not culpable in the administration’s wider, sinister designs.

In fact, Tenet’s book and his TV comments serve as shocking indictments of his and his agency’s failings, which only helped fuel a pre-existing Bush administration lust for Saddam’s head. Bush was committed to following the Iraq-invasion playbook of the unilateralist lunatics of the Project for a New American Century long before a case was made, one way or the other, for WMDs.

As I noted in my column on February 6, 2003, the Powell exhibition at the U.N. Security Council was simply “to sway public opinion, especially in the U.S., in favor of a unilateral U.S. invasion of Iraq.” Otherwise, there was no purpose in exposing U.S. intelligence methods and means in such a setting, when it should have been done in a closed-door session. As video footage of that fiasco show, George Tenet was sitting right behind Powell, nodding in the affirmative, as the ostensible “case” was made.

“It was highly doubtful that a single vote on the Security Council was changed by Powell’s speech yesterday. He did not convince anyone not already convinced why a preemptive military intervention, rather than a stepped up policy of inspections, weapons destruction and containment, has to be the only way to go,” I wrote.

The column cited a commentary in the February 2, 2003 New York Times by the University of Chicago’s John J. Mearsheimer and Harvard’s Stephen M. Walt, entitled, “Keeping Saddam Hussein in a Box.” They noted that “Iraq has never gone to war in the face of a clear deterrent threat,” adding, “Weapons of mass destruction do not pose either a real or blackmail threat when Hussein knows the consequences of their use would be his total annihilation.”

Additionally, they cited the “costs of war versus containment.” How right on target they were.

But only now, in the hindsight provided by his new book, do we see fully how amazingly pathetic Tenet’s assessment of WMDs really was at the time, by his own admission. It is stunning that in his explanations on TV, he doesn’t seem phased by the obvious flimsiness of that errant assessment, especially in light of the consequences that have flowed from it. He’s arguing defensively that it was credible, but therein was his eternal disservice to humanity.

Start from the realization now, for years now actually, that, of course, the assessment was, in point of fact, flat wrong.

How does he explain that the assessment was offered, then? It clearly was not on the basis of any solid facts, since there were none. In an almost unbelievable confession, Tenet told Wolf Blitzer of CNN in a TV interview yesterday that it was based not on anything that the CIA knew, but on what it didn’t know.

“We didn’t want what we don’t know to cause us to be surprised,” he said.

That’s the bottom line, the cause of all the misery of the last four years in Iraq. It was based not on intelligence, but the lack of it. It was justified, as Tenet said in his own words, by “what we don’t know.”