The unbelievers.

Byline: The Register-Guard

Of all the things that have transpired in the five years since the devastating terrorist attacks of Sept. 11, 2001, easily the most astounding is the fact that a growing number of Americans don't believe the official Bush administration version of what actually happened on "the day that changed everything."

The nation's response to the cataclysmic shock of those attacks included wars that continue to this day with no end in sight. Yet millions of American citizens fiercely dispute the explanation they were given for who and what caused the tragedy.

Thirty-six percent of the public responding to a recent poll by Ohio University and Scripps Howard News Service said they believe that government officials "either assisted in the 9/11 attacks or took no action to stop the attacks because they wanted the United States to go to war in the Middle East."

The same poll found that 12 percent of Americans believe a cruise missile fired by the U.S. military caused the damage at the Pentagon - not an American Airlines jet hijacked by Arab terrorists. Sixteen percent of Americans believe that "secret explosives" really caused the collapse of the World Trade Center towers - not two burning planes and the damage resulting from their crashes into the skyscrapers.

The truth is that even more Americans would likely join the growing Sept. 11 conspiracy movement if they saw the videos and visited the authoritative Web sites that challenge the official version of events. Dylan Avery's slick film "Loose Change" casts doubt on every aspect of the government's explanation that 19 al-Qaeda terrorists under the direction of Osama bin Laden were behind the attacks. "Loose Change," which is available for free viewing on the Google Video and YouTube Web sites, has become one of the most-watched movies on the Internet, racking up 10 million viewers in the past year alone.

Like all conspiracy movements, the Sept. 11 "truth activists," as they like to be known, have their share of crackpots. But they also have powerful advocates such as Robert Bowman, a former U.S. Air Force lieutenant colonel with a doctorate from the California Institute of Technology who directed the "Star Wars" defense program under presidents Gerald Ford and Jimmy Carter.

"It's hard to believe that somebody at some (government) level wasn't complicit in this thing," Bowman told a San Francisco Chronicle reporter in an interview last week. Bowman's personal experience and background leave him with huge doubts about the official explanations for why military aircraft didn't intercept the hijacked planes. And he points to a paper published in 2000 by the neoconservative Project for the New American Century that has become one of the Sept. 11 conspiracy movement's smoking guns.

PNAC counts among its members a who's who of Bush administration insiders, including Defense Secretary Donald Rumsfeld, his former deputy Paul Wolfowitz and Vice President Dick Cheney. The paper, titled "Rebuilding America's Defenses," was the first to use the term "a new Pearl Harbor" to characterize the kind of catastrophic event that it would take to unite Congress, the military and the American people behind a military effort to reassert U.S. authority around the globe. Within hours of occurring, the Sept. 11 attacks were widely being called "a new Pearl Harbor" by news media and government officials.

Among other credible skeptics of the official explanation is Scholars for 9/11 Truth, a loose-knit group of academics who have assembled a comprehensive Web directory of Sept. 11 information at www.scholarsfor911truth.org.

Conspiracy theories only work if they're plausible, and the Sept. 11 theories don't disappoint in that regard. But they are aided by a widespread belief that the Bush administration suffers from serious credibility problems, particularly associated with the post-Sept. 11 war on terror.

The list of debunked administration assertions is too long to cite here. They range from the false but still-implied link between Saddam Hussein and the Sept. 11 attacks to statements such as the one issued in March by Joint Chiefs of Staff Chairman Gen. Peter Pace, who said in response to a question about how things were going in Iraq, "I would say they're going very, very well from everything you look at."

Despite the administration's credibility problems, the official explanation of Sept. 11 events has plenty of independent corroboration. Numerous books and studies have been written debunking key elements of the conspiracy theories. Two were released last week, one by the State Department and another by a federal science agency.

The best reason to doubt the dark vision of the Sept. 11 conspiracists doesn't depend on a belief that the U.S. government would never lie to the American people. It's based on a more fundamental failing of government, best articulated by former White House terrorism adviser Richard Clarke in a blurb for the Popular Mechanics book, "Debunking 9/11 Myths: Why Conspiracy Theories Can't Stand Up to the Facts."

"Despite the fact that the myths are fictitious, many have caught on with those who do not trust their government to tell the truth," Clarke said. "Fortunately, the government is not sufficiently competent to pull off such conspiracies and too leaky to keep them secret."