Bin Laden, the son of a Saudi building tycoon, said he did not have the means to organise terrorist attacks because of restrictions placed on his contacts with the outside world by Taleban leader Mullah Omar.
The FBI has found names and details of the 19 hijackers who attacked America last Wednesday morning but proving direct links strong enough to refute bin Laden's denials is difficult, say intelligence officials in the US.
Officials have admitted the Bush Administration has virtually no good intelligence in Afghanistan and is in the difficult position of relying on foreign Governments in the Muslim world for information.
In addition, the FBI's search for the perpetrators has seen them pursue thousands of leads but also get caught in a maze of false ones and unsuccessful searches.
It has turned out that one of the 19 names issued by the Justice Department in its list of suspects last week belongs to a pilot for Saudia, the national airline of Saudi Arabia.
He lives in Jeddah, in Saudi, and his papers could have been stolen.
The main suspects may have shared a hatred of the West and a common religion but a shared religion is not proof.
History has proven that it is unlikely that any of those involved actually ever met bin Laden.
The 1993 World Trade Center bombing in New York, which left six dead and hundreds hurt, and the 1998 bombing of the US embassies in Kenya and Tanzania, which killed 235 and injured 5500, have both been linked to bin Laden.
The Observer newspaper has reported that for the Nairobi operation teams comprised a mix of "sleepers" who had been in Kenya for some time and those who had never been on a terrorist operation before.
The same structure is now being uncovered in America.
It has become apparent that bin Laden's group is neither a traditional hierarchical organisation with a leader, deputies and a cell structure, nor merely an association of vaguely like-minded, loosely affiliated individuals.
Al Qaeda does not act as a commander, it acts as a facilitator putting together disparate elements - some in Afghanistan and some in the target country or other locations entirely - who can pull off the operations, the Observer said.
A bin Laden terrorist "cell" was recently on trial in Jordan. But the only link with him was a signature scrawled on a piece of paper by one defendant - a Palestine-born naturalised American Boston taxi driver.
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