CHICAGO, June 4 — In the ballroom foyer of the Embassy Suites Hotel, the two-day International Education and Strategy Conference for 9/11 Truth was off to a rollicking start.
In Salon Four, there was a presentation under way on the attack in Oklahoma City, while in the room next door, the splintered factions of the movement were asked — for sake of unity — to seek a common goal.
In the foyer, there were stick-pins for sale ("More gin, less Rummy"), and in the lecture halls discussions of the melting point of steel. "It's all documented," people said. Or: "The mass media is mass deception." Or, as strangers from the Internet shook hands: "Great to meet you. Love the work."
Such was the coming-out for the movement known as "9/11 Truth," a society of skeptics and scientists who believe the government was complicit in the terrorist attacks. In colleges and chat rooms on the Internet, this band of disbelievers has been trying for years to prove that 9/11 was an inside job.
Whatever one thinks of the claim that the state would plan, then execute, a scheme to murder thousands of its own, there was something to the fact that more than 500 people — from Italy to Northern California — gathered for the weekend at a major chain hotel near the runways of O'Hare International. It was, in tone, half trade show, half political convention. There were talks on the Reichstag fire and the sinking of the Battleship Maine as precedents for 9/11. There were speeches by the lawyer for James Earl Ray, who claimed that a military conspiracy killed the Rev. Dr. Martin Luther King, and by a former operative for the British secret service, MI5.
"We feel at this point we've done a lot of solid research, but the American public still is not informed," said Michael Berger, press director for 911Truth.org, which sponsored the event. "We had to come up with a disciplined approach to get it out."
Mr. Berger, 40, is typical of 9/11 Truthers — a group that, in its rank and file, includes professors, chain-saw operators, mothers, engineers, activists, used-book sellers, pizza deliverymen, college students, a former fringe candidate for United States Senate and a long-haired fellow named hummux (pronounced who-mook) who, on and off, lived in a cave for 15 years.
The former owner of a recycling plant outside St. Louis, Mr. Berger joined the movement when he grew skeptical of why the 9/11 Commission had failed, to his sense of sufficiency, to answer how the building at 7 World Trade Center collapsed like a ton of bricks. It was his "9/11 trigger," the incident that drew him in, he said. For others, it might be the fact that the air-defense network did not prevent the attacks that day, or the appearance of thousands of "puts" — or short-sell bids — on the nation's airline stocks. (The 9/11 Commission found the sales innocuous.)
Such "red flags," as they are sometimes called, were the meat and potatoes of the keynote speech on Friday night by Alex Jones, who is the William Jennings Bryan of the 9/11 band. Mr. Jones, a syndicated radio host, is known for his larynx-tearing screeds against corruption — fiery, almost preacherly, addresses in which he sweats, balls his fists and often swerves from quoting Roman history to using foul language in a single breath.
At the lectern Friday night, beside a digital projection reading "History of Government Sponsored Terrorism," Mr. Jones set forth the central tenets of 9/11 Truth: that the military command that monitors aircraft "stood down" on the day of the attacks; that President Bush addressed children in a Florida classroom instead of being whisked off to the White House; that the hijackers, despite what the authorities say, were trained at American military bases; and that the towers did not collapse because of burning fuel and weakened steel but because of a "controlled demolition" caused by pre-set bombs.
According to the group's Web site, the motive for faking a terrorist attack was to allow the administration "to instantly implement policies its members have long supported, but which were otherwise infeasible."
The controlled-demolition theory is the sine qua non of the 9/11 movement — its basic claim and, in some sense, the one upon which all others rest. It is, of course, directly contradicted by the 10,000-page investigation by the National Institute of Standards and Technology, which held that jet-fuel fires distressed the towers' structure, which eventually collapsed.
The movement's answer to that report was written by Steven E. Jones, a professor of physics at Brigham Young University and the movement's expert in the matter of collapse. Dr. Jones, unlike Alex Jones, is a soft-spoken man who lets his writing do the talking. He composed an account of the destruction of the towers (www.physics.byu.edu/research/energy/htm7.html) that holds that "pre-positioned cutter-charges" brought the buildings down.
Like a prior generation of skeptics — those who doubted, say, the Warren Commission or the government's account of the Gulf of Tonkin attack — the 9/11 Truthers are dogged, at home and in the office, by friends and family who suspect that they may, in fact, be completely nuts.
"Elvis and Area 51 — we're sort of lumped together," said Harlan Dietrich, a recent college graduate from Austin, Tex. "It's attack the messenger, not the message every time."
To get the message out, the movement has gone beyond bumper stickers and "Kumbaya" into political action.
There is a plan, Mr. Berger said, to create a fund to support candidates on a 9/11 platform. There is a plan to create a network of college campus groups. There is a plan by the British delegation (such as it is, so far) to get members of Parliament to watch "Loose Change," the seminal movement DVD.
It would even seem the Truthers are not alone in believing the whole truth has not come out. A poll released last month by Zogby International found that 42 percent of all Americans believe the 9/11 Commission "concealed or refused to investigate critical evidence" in the attacks. This is in addition to the Zogby poll two years ago that found that 49 percent of New York City residents agreed with the idea that some leaders "knew in advance" that the attacks were planned and failed to act.
Beneath the weekend's screenings and symposiums on geopolitics and mass-hypnotic trance lies a tradition of questioning concentrated power, both in public and in private hands, said Mark Fenster, a law professor at the University of Florida and author of "Conspiracy Theories: Secrecy and Power in American Culture."
As for the 9/11 Truthers, they were confident enough that their theories made sense that on Friday, as a kickoff to the conference, they met in Daley Plaza for a rally (though some called it Dealey Plaza). They marched up Kinzle Street to the local affiliate of NBC where, at the plate glass windows, they chanted, "Talking heads tell lies," as the news was being read.
"I hope you don't end up dead somewhere," a companion said to a participant, hours earlier as he dropped him at the Loop. "Don't worry," the participant said. "There's too many of us for that."