With the upcoming release of the film "United 93," the terrorist attacks of Sept. 11, 2001, have returned to the fore of public consciousness. While for many Americans such painful memories remain forever seared in their minds, for a small but vocal minority the Sept. 11 attacks have taken on a mythical character. These are the Sept. 11 conspiracy theorists.

If Web sites such as whatreallyhappened.com, 911truth.org and scholarsfor911truth.org (among countless others) are any indication, the Sept. 11 conspiracists have become a movement in their own right. Despite a host of differences, they share the belief that the widely accepted version of what happened on Sept. 11 is merely a front for a shadowy plot to fool the American people.

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