"The official version is only propaganda... What caused the explosion at the Pentagon? What became of American Airlines Flight 77? Are the passengers dead? If so, who killed them, and why? Otherwise, where are they? These are the questions the American administration must answer."

Which country spawned these conspiratorial rantings about September 11? Syria? Saudi Arabia? Iraq? No; the paranoid fantasy above is extracted not from the statesponsored media of some virulently anti-American dictatorship, but from a book being snatched up like petits pains by our purported allies: the French. The Dreadful Imposture, by left-wing activist Thierry Meyssan, is a thin--and thinly argued--volume that claims the Pentagon was struck not by an airplane but by a truck bomb planted by rogue U.S. military officers. It calls Osama bin Laden a Central Intelligence Agency (CIA) stooge and suggests that 9/11 was the culmination of a long-planned military-industrial complex coup to justify a dramatic increase in defense spending and an invasion of Afghanistan. How seriously are the French taking Meyssan's theories? His book has sold over 100,000 copies. And last week it became the country's number-one nonfiction best-seller.

Here, briefly, is the evidence upon which Meyssan's theory rests: There are no images of an aircraft striking the Pentagon, and the images of the alleged crash site show no wreckage from a plane. Yet if, as the Pentagon claims, the nose of Flight 77 entered the first few rings of the building, parts of the fuselage and the wings should have been strewn across the lawn. All this is, in a literal sense, true: No photos have been published showing the plane striking the Pentagon and, because Flight 77 virtually disintegrated on impact, there was very little identifiable plane wreckage. Which might raise legitimate questions, had numerous eyewitnesses not seen the crash. To Meyssan, however, the eyewitnesses simply reveal the extent of the cover-up. "Notwithstanding the respect we owe to the high quality of the 'eyewitnesses,' officers and legislators, it is impossible to swallow such nonsense," Meyssan writes. "Far from lending credit to their testimony, the quality [i.e., high status] of these witnesses only underlines the importance of the means deployed by the United States Army to disguise the truth." Meyssan goes on to speculate that the government planted beacons in the World Trade Center to help the other two planes reach their targets and planted explosives at the base of the towers to ensure their collapse. In his opinion, bin Laden, a longtime CIA operative and friend of the Bush family, cooperated in the plot. What motivated all this deception? The militaryindustrial complex (the same people, Meyssan notes, who killed John F. Kennedy) needed a pretext to mount a "colonial expedition" into Afghanistan to secure an oil pipeline through Central Asia and to impose martial law in the United States and dominate the world.

Meyssan first posted his "revelations" on the Internet almost immediately after September 11, where they quickly followed the arc of all successful Web hoaxes, their diffusion growing exponentially through word of mouth, links, and e-mails. The French press noted the theory, but mainly as an Internet phenomene. But when Meyssan began appearing on television to promote the book version of his argument--published in late March by Editions Carnot, an obscure publishing house specializing in outlandish conspiracy theories--the country's most prominent newspapers and magazines began devoting hundreds of column inches to shooting it down. "As the controversy gathered steam, my editors kept insisting that I write something about it," says Pascal Riche, Washington bureau chief of the leftist newspaper Liberation. "I was dragging my feet and there was a debate with the newsroom over whether this was worthy of being debunked." Ultimately the book's popularity forced Riche and many other prominent French journalists to weigh in. And of course, in taking Meyssan on, they gave his views wider distribution. Jean-Bernard Cadier, Washington bureau chief for Europe 1, the largest news and talk radio network in France, recalls the Alice-in-Wonderland quality of a TV panel he appeared on with five other mainstream journalists--and Meyssan. "We were six against him, and I'm sure we lost," he said. "He's not using the same weapons we are."

One reason meyssan's views have been taken seriously is that he does not have a prior reputation as a nut. As head of Reseau Voltaire, a hitherto respectable organization devoted to promoting civil liberties, he has scored some worthy journalistic coups with investigations of Opus Dei and the far-right National Front; and he has earned a well-established place within the mainstream left with his campaigns for gay rights and the separation of church and state.

But there are deeper reasons, which have their roots in French culture. The unimaginable terrorist attacks, the French sociologist Pierre Lagrange has said, confronted people with a reality so close to science fiction that it sparked a flowering of "revisionist" or paranoid interpretations similar to those that arose after the Holocaust, the Kennedy assassination, and the moon landing. Meyssan, who in addition to his rabid anti-Americanism clearly suffers from a very French propensity toward excessive rationalism, went out in search of a theory that in strict logical terms "makes sense." His approach to the improbable truth of what happened on September 11 resembles the one taken by a French engineer who traveled to Britain in the early 1800s to inspect the newly developed steam locomotive. According to a story that has become part of French legend, he watched it pass before him on a short length of track, took out a pad and paper, did a series of calculations, and announced: "ea ne marche pas."

But of course, the primary reason for Meyssan's celebrity is the insatiable appetite many in France have for things anti-American. Although recent polls show that strong anti-American feelings only resonate with between 10 percent and 15 percent of respondents--roughly the same percentage of the population drawn to extremist political parties on the right and left--the book's popularity suggests that the number of people willing to entertain anti-American theories is far higher. After an initial outpouring of sympathy, the perceived unilateralism of America's response to September 11 has lifted the lid on long-simmering resentments stemming from France's reduced presence in geopolitics and a fear of American "hyperpower" (in the phrase of French foreign minister Hubert Vedrine). "It's a reaction to the events," says Cadier. "The empathy has been transformed into the feeling that the U.S. is taking advantage of the situation to throw its weight around." In fact, no pretext is now too petty to justify anti-American paranoia. When Amelie failed to win an Oscar, some commentators claimed it was payback for France's resistance to war against Iraq. When a madman killed eight people in late March in a suburb of Paris, a presidential candidate at the scene called the rampage a pathology "a l'Americaine." Some in France have even suggested that Meyssan's book itself is a CIA plot to discredit French resistance to American hegemony. If so, the plot is working very nicely indeed.

Max Berley is an editor on the foreign desk of The Washington Post.

By Max Berley