The idea for the spectacular attacks was the brainchild of Khalid Shaikh Mohammed. The Kuwaiti-born, U.S.-educated militant -- now in U.S. custody -- had first floated it to bin Laden in 1996.
Three years later, in a meeting in the southern Afghan city of Kandahar, the Al-Qaeda leader gave his answer: bin Laden told Mohammed he would back the audacious proposal.
That meeting set in motion a whirlwind series of events that would lead to the 11 September 2001 attacks on the United States, which killed 2,800 people.
The episode is just one of many gripping details to emerge from two preliminary staff reports released yesterday in Washington by the independent National Commission on Terrorist Attacks Upon the United States, better known as the 9/11 Commission. The final report is due out in July.
While most of the details involve the planning of the attacks and thinking of top Al-Qaeda figures, including bin Laden, the U.S. media have focused on another aspect of the reports. In a conclusion likely to put pressure on U.S. President George W. Bush ahead of November's election, the panel said there is no evidence Iraq ever aided Al-Qaeda in its attack against the U.S.
This is what former CIA Deputy Director Douglas MacEachin told the commission yesterday. "We have no credible evidence that Iraq and Al-Qaeda cooperated on attacks against the United States," MacEachin said.
The panel noted evidence of contacts between Al-Qaeda and Iraq going back some years, but said these did not appear to have resulted in a collaborative relationship. "At that time , bin Laden is said to have requested space for training camps, assistance in procuring weapons, but Iraq apparently never responded. There have been reports that contacts between Iraq and Al-Qaeda also occurred after bin Laden returned to Afghanistan, but they do not appear to [have] resulted in a collaborative relationship," MacEachin said.
That finding contradicts claims by some members of the Bush administration, including a comment by Vice President Dick Cheney on 14 June, that former Iraqi President Saddam Hussein had long-established ties with Al-Qaeda. Bush himself, however, has admitted the administration has no evidence Hussein was involved in the 9/11 attacks.
The commission also says an alleged meeting in Prague between 9/11 pilot Mohammed Atta and an Iraqi intelligence officer never took place.
Cheney has repeatedly cited the purported meeting in April 2001 as evidence of a link between Iraq and Al-Qaeda. But the panel reports say there are videos of Atta withdrawing money from a bank in Virginia during that time, as well as records of cell-phone calls he made in the United States.
The commission based its findings on some 1,100 interviews in 10 countries. The bulk of the panel's insights appear to have come from transcripts and summaries of government interviews with detainees, chief among them Khalid Shaikh Mohammed.
Among other details that contradict previous reports, the panel says bin Laden is not nearly as wealthy as was thought. He never inherited $300 million and he was apparently cut off in 1994 from a yearly family stipend of $1 million.
And contrary to many media reports, the panel found no evidence of Saudi government funding to Al-Qaeda, whose finances apparently come mainly from Muslim charities and private donors.
As for the 9/11 plans, the reports say Mohammed first began discussing them in the early 1990s with his uncle, Ramzi Yousef, the architect of the first World Trade Center bombing in 1993.
Mohammed originally plotted to blow up 12 U.S. airliners over the Pacific in 1995, but Philippine authorities foiled the plan.
After he proposed a 9/11 scenario to bin Laden in 1996, the reports say Al-Qaeda militants training in camps in Afghanistan were given free rein "to think creatively about ways to commit mass murder." Their ideas included seizing a launcher in Russia in order to force scientists to fire a nuclear missile at America as well as launching gas or cyanide attacks on Jewish areas in Iran.
Mohammed's original 9/11 plan involved hijacking 10 jets simultaneously and striking skyscrapers in California and Washington state, as well as U.S. targets in Japan, South Korea, and Singapore. But bin Laden rejected such plans, arguing they would be too hard to coordinate, and opted to focus on New York and Washington.
There were other disagreements within Al-Qaeda as well. Bin Laden, apparently impatient to strike America, pushed to launch the attacks as early as 2000. But he was rebuffed in turn by Mohammed, who wanted more time to plan and train the pilots.
Other Al-Qaeda leaders argued against the attacks altogether, as did Taliban chief Mullah Omar, who apparently feared U.S. retaliation against his regime and harming its ties with Pakistan, then one of just three nations to have diplomatic ties to Kabul.
Also, Omar's regime apparently received $10 million to $20 million a year in aid from Al-Qaeda in exchange for sheltering the terrorist network.
Until two days before the 9/11 attacks, the plotters may still have disagreed about targets. They agreed on attacking the World Trade Center and the Pentagon as symbols of U.S. economic and military power. But while bin Laden insisted on hitting the White House, Atta argued for striking the U.S. Capitol building, believing the White House to be too hard a target to hit.
Atta also is reported to have said he would crash his jet into the streets of New York if he were unable to strike a World Trade Center tower.
Meanwhile, the commission reports found direct involvement of bin Laden in the 1993 downing of a U.S. helicopter in Somalia, which killed 18 U.S. soldiers and sparked a U.S. withdrawal from the country that Al-Qaeda touted as proof America could be forced to retreat.
The reports also found evidence of bin Laden involvement in the 1996 attack on the Khobar Towers in Saudi Arabia, which killed 19 Americans. That attack has been blamed on Hezballah and the panel says it found "multiple signs of collaboration" between that Iranian-backed group and Al-Qaeda.