Ahmed Ressam , the captured al-Qaeda Millennium Bomber , was at the time sharing information with the US authorities , in an effort to gain leniency in his sentencing . One person whom he was not asked about until after 9/11 , but whom he was able to identify when asked as having trained with him at al-Qaeda 's Khalden Camp in Afghanistan , was Moussaoui . The 9/11 Commission Report opined that had Ressam been asked about Moussaoui , he would have broken the FBI 's logjam . Had that happened , the Report opined , the U.S. might conceivably have disrupted or derailed the September 11 attacks altogether
September 11 attacks
September 11 attacks
Zacarias Moussaoui