Now that everyone's sure that Osama bin Laden's our man, it might be time to take a step back and ask, How do we know?

And the answer is, we "know" because Washington says that who's behind the September 11th attacks.

But given Washington's track record on telling the truth --especially when it comes to reasons for initiating wars --  a sane person might treat this claim with a healthy dollop of scepticism.

Ask yourself, What evidence is there available to the average person on the street, people like you and me, that bin Laden is responsible?

The answer, if you think about it for a moment, is that there is no evidence.  Just innuendo, circumstantial indication, and possibilities. And appeals to "trust us." But nothing firm or concrete.

Washington  can't even advance a lame case for bin Laden's involvement, let alone a compelling one. Secretary of State Colin Powell reneges on his promise to present the evidence, the best Deputy Secretary of Defense Paul Wolfowitz can do is contend that "the evidence is there for the whole world to see" and NATO chief Lord Robertson opines that allies don't need to see any evidence. The Toronto Globe and Mail says, "The United States said it is certain that Mr. bin Laden is the mastermind behind the attacks. But after three  weeks, the information revealed about ties between Mr. bin Laden and the 19 hijackers is tenuous and circumstantial."  The newspaper might have added, tenuous and circumstantial at best.

British Prime Minister Tony Blair, whose frequent dalliances with prevarication, equivocation, and paltering with the truth, make him a dubious poster boy for the virtues of truth-telling, says reassuringly, "I have seen absolutely powerful, incontrovertible evidence of (bin Laden's) link to the events of September 11." Of course, Blair can't share it with us. We're supposed to trust him.

That Washington has incontrovertible, powerful evidence, or that Blair has seen it, seems doubtful. Consider: Prior to the attacks, the US intelligence community said there were seven states of concern that sponsor terrorism: Iraq, Iran, Libya, Sudan, Cuba, Syria and North Korea. Somehow they missed Afghanistan, which, if you believe the stories, is now, and was ,the world's largest breeding ground of terrorists. So how is it that this vaunted intelligence apparatus can miss the world's largest hotbed of terrorism, yet in the space of three weeks amass compelling and powerful evidence linking bin Laden to the attacks? And how is it that an intelligence community that can assemble powerful evidence implicating bin Laden in just three weeks, was so spectacularly unsuccessful in anticipating the attacks?

And there's the question, Why has no one claimed responsibility for the terror? Isn't that the point of terror attacks? To make plain who's behind them, and why? So why does bin Laden keep saying he  wasn't the guy?

Still, if bin Laden won't step forward to take responsibility, pointing to reason x, y and z for arranging terror attacks on thousands of innocent people, others have. Washington's conveniently filled in the blanks on who (bin Laden) and others are conveniently filling in the blanks on why (bin Laden's pissed off over Israeli repression of Palestinians, the Gulf War, the US military presence in Saudi Arabia, and sanctions against Iraq.)  What's significant here is the alleged perpetrator isn't providing any of the answers. Others are. So while bin Laden's involvement is a possibility, and while he may have a motive,  all we know is that a whole lot of other people think he did it, but don't seem to wonder why bin Laden isn't claiming responsibility.

More frightening to contemplate is the hypothesis that the US or allied governments were involved --- also a possibility. If you ask the question, Who benefits from the attacks? and consider the history of Washington engineering numerous casus belli, while still frightening to contemplate, the hypothesis is far from outlandish. The Gulf of Tonkin affair -- a phoney attack on the USS Maddox -- was the sole basis for Washington's decision to initiate a war in Vietnam that left close to 50,000 American GIs dead, and ushered three million inhabitants of Indochina into early graves. Lying in the service of war-making has happened so often in the past it might as well be called a Washington tradition.

Still, the analysis surrounding the events of September 11 is unfolding much as the analysis around Yugoslavia did, and before that, the Vietnam War: that is, without consideration of the possibilities, and without the healthy dollop of scepticism the situation calls for, or recognition that most of the claims advanced so far rest on a weak evidentiary foundation, if any at all.

In the case of the NATO air war against Yugoslavia, the media said Milosevic, then the country's president, was a dictator, a brute, a murderer. They pointed to the Racak massacre, the alleged killing of dozens of ethnic Albanians by Serb police at the Kosovar village of Racak, to justify the bombing of Yugoslavia. And yet French press reports at the time cast doubt on whether the massacre actually happened, pointing to the possibility that it was staged by the KLA, with the involvement of Washington. OECD observers, present at Racak on the day of the alleged massacre, made no mention of it. And forensic pathologists who investigated the massacre on behalf of the EU later said there was no evidence that a massacre had actually occurred, but that the US official present at the scene, William Walker, was quick to conclude that one had indeed occurred.

Walker's case was helped along by the chattering classes, who, almost to a person, condemned the Racak attack, thereby establishing the event as fact.  Few questioned it. This was true, too, of the administration's fiercest critics, who disagreed with Washington's decision to bomb Yugoslavia, but conceded that Racak was terrible.  Accordingly, the claims that formed the basis of the rationale for intervention were accepted as true, by both critics and supporters of the administration.

There's a psychology that grips us in these circumstances. Rally around the flag. Rally around our leaders. Now's the time to support our country -- "country" and "government" being mistakenly conflated. And even those who reject this dangerous chauvinism soon find themselves in the grips of another psychology -- herd thinking. Everyone says "x," so you go along. You say, "I don't remember seeing anything that proves "x" but maybe I wasn't paying attention. Maybe the evidence is staring me in the face and I'm too stupid to see it. But everyone else seems to see it so I guess it must be true."

Of course, everyone else is thinking exactly the same thing, too, so  "x" comes to be widely accepted, not on the basis of any evidence, but simply because it's widely accepted.  People like Wolfowtiz can then say, "What do you need evidence for? It's staring you in the face." And, for good measure, anyone who questions the received wisdom is dismissed as a nut case, a conspiracy theorist -- epithets most people will bend over backwards to avoid

Not surprisingly, in the aftermath of September 11th, the same processes that led the American people into the disasters of the Vietnam war, into supporting the bombing of Yugoslavia, are at work again. Washington says bin Laden is responsible, and before you know it, everyone says bin Laden's responsible, including the administration's most energetic critics. And yet the stories that hold bin Laden responsible are all as tenuous as the stories about the Racak massacre, or the Gulf of Tonkin affair. Even people who know about how the American people have been duped by their governments over and over again,  stretching back to the stealing of California from Mexico, immediately put out of their minds the possibilities that their government is lying, or worse, is involved. The latter claim is too terrible to contemplate. But is it so outlandish that governments would commit horrific acts that ordinary people consider too wicked, too depraved, too unconscionable to credit?

Hitler said that you could safely tell huge lies to ordinary people, because they themselves would never tell lies so huge, and therefore wouldn't believe that their government could. He could have said that governments could commit acts so despicable that ordinary people would never believe the acts had really been committed, because they could never commit such wicked acts themselves, and therefore wouldn't believe their governments could.

But think of our history. One may have thought the dropping of atomic bombs on Hiroshima and Nagasaki was too terrible to contemplate, but it happened. The firebombing of Tokyo was too terrible to contemplate, but it happened, too. And also the carpet-bombing of Korea and Indochina , the death through sanctions of over a million Iraqis, and the Gulf War. And one might have thought the idea of engineering terror attacks on American targets and pinning the blame on the Cubans to justify an invasion of Cuba  would be too terrible to contemplate, but that, apparently, was contemplated in 1962 by the five Joint chiefs, according to James Bradford's study of the National Security Agency, Body of Secrets (Doubleday). Nothing it seems -- and this is the frightening part -- has ever been too terrible for Washington to contemplate.

But try as you might to keep a clear head, it's hard to resist the insidious lure of the lies. There are traps lurking in everything you read. A glaring example: A newspaper I read reported that many Muslims point to, what the newspaper described as, "the unsubstantiated rumor" that Israeli intelligence was behind the attacks. To be sure, the claim is unsubstantiated, and has the character of a claim that would be comforting for some to believe. But the newspaper didn't point out that bin Laden being behind the attacks is just as much an unsubstantiated rumor, and equally, has the character of a claim that's comforting for some people to believe. Instead, the report treats bin Laden's involvement as fact, as substantiated (despite bin Laden's own denials and Washington's failure to produce any evidence) and treats all alternative explanations as unsubstantiated.

In a similar vein, The New York Times deals with demands from US allies to produce evidence that bin Laden was involved with this line, "But administration officials are still debating how much information to make public since much of it rests on secret communications intercepts," thus implicitly declaring that the administration does have evidence, and dismissing the equally tenable hypothesis that it has none at all, and is hiding behind "security considerations."

Perhaps even more disconcerting than possibilities that are too terrible to contemplate, is the absence of explanation, the admission that we don't know who's behind the September 11th attacks, and that the answers Washington offers may be  no more than what Washington produces in abundance: lies, in the service of something else Washington produces in abundance: violence.

I'm not saying bin Laden isn't involved. Nor am I saying that Washington is. And neither am I ruling out the possibility that both bin Laden and Washington are involved, or aren't. What I am saying, though, is that we've been lied to before, over and over. To accept Washington at its word again, without asking questions, to believe what the media and everyone else seems to believe simply because everyone seems to believe it, would be a mistake. Our willingness to rally around the flag, to suspend our scepticism, to avoid asking questions for fear of being unpatriotic, has led us into disaster before. It will again.

As American historian Howard Zinn says, "The most patriotic act in times of war is to ask questions." It's time for patriots to ask questions.

Mr. Steve Gowans is a writer and political activist who lives in Ottawa, Canada.