911 FULL ORIGINAL VIDEOSeptember 11, 2001 attacks, a variety of conspiracy theories have emerged about the attacks which contradict the mainstream account of events that day. The theories typically include suggestions that individuals in the government of the United States knew of the impending attacks and refused to act on that knowledge, or that they played a role in the attacks. Conspiracy theorists have claimed that the collapse of the World Trade Center was the result of a controlled demolition. Some also contend that a commercial airliner did not crash into the Pentagon, and that United Airlines Flight 93 was shot down. The scientific community does not support the controlled demolition hypothesis and U.S. officials, mainstream journalists, and researchers have concluded that only al-Qaeda was involved in the attacks.The collapse of the World Trade Center was a surprise to the engineering community. While no skyscraper had ever before completely collapsed due to fire or other...