Why do you insist that September 11, 2001 was one incident unrelated to any prior events?
Actually, there really was life, terrorist activity against the United States, and history before September 11, 2001.
Many of us were nearly certain on 9-11-01 that bin Laden was the perpetrator that day because of the known 'pattern' of bombings of the USS Cole, the US embassies in Kenya and Tanzania, and the 1993 bombing of the WTC--all of which have established his connections to those events.