It's been five years since the terrorist attacks on the World Trade Center and the Pentagon -- yet a growing chorus of conspiracy theorists accuses the U.S. government of carrying out the attacks. Popular Mechanics executive editor David Dunbar, contributing editor Brad Reagan and editor-in-chief Jim Meigs joins me for a detailed discussion of reporting behind the new Popular Mechanics book Debunking 9/11 Myths: Why Conspiracy Theories Can't Stand Up To Hard Facts in this special edition of The Popular Mechanics Show. Also joining us to help walk us through a detailed analysis of World Trade Center conspiracy theories is former Deputy Fire Chief of the New York City Fire Department Vincent Dunn. Less