Bin Laden provided leadership and financial support for the plot, and was involved in selecting participants.  Bin Laden initially selected Nawaf al-Hazmi and Khalid al-Mihdhar , both experienced jihadists who had fought in Bosnia . Hazmi and Mihdhar arrived in the United States in mid-January 2000. In spring 2000, Hazmi and Mihdhar took flying lessons in San Diego, California , but both spoke little English, performed poorly with flying lessons, and eventually served as secondary – or "muscle" – hijackers.  
Either the Bush Administration is lying, or most of America’s close allies are. So why hasn’t Congress investigated these foreign intelligence claims? Why hasn’t a single mainstream media article connected all these dots, or given these warnings the coverage they deserve? Either some people within the US government knew the 9/11 attack would happen and did nothing, or some people within the US government failed to heed advice from a dozen foreign governments and properly defend the US from attack. Perhaps both. These people should be removed from office on the grounds of gross incompetence, or face the legal consequences of aiding and abetting terrorism. It seems clear that there are people who fear an investigation, and that that is why these dots are left unconnected.