Moussaoui trial fills in details of 9/11 plot

The boss talked too much. Some underlings were unreliable. The big project got under way before its plan was finished.

Sound like a typical office? It wasn't. These are details about the formulation of the Sept. 11 plot, provided by someone who would know: Khalid Sheikh Mohammed, Al Qaeda official and terrorist mastermind.

A key piece of evidence in the sentencing trial of Zacarias Moussaoui is a 58-page deposition from Mr. Mohammed, who was captured in Pakistan in 2003. While it does offer some insight into Mr. Moussaoui's place in the Al Qaeda hierarchy, the document is perhaps most interesting for its depiction of how the Sept. 11 conspiracy unfolded.

The deposition fills in some blanks from previous accounts - while depicting the strengths and weaknesses of what might be called "Al Qaeda Inc."

"Khalid Sheikh Mohammed was a great intelligence find, and we learned a lot from him," says William Martel, a professor of international security studies at the Fletcher School at Tufts University in Medford, Mass.

By his own account, Mohammed never rose to the highest Al Qaeda inner council. But he was still a top official, at the end - chief of external relations. And he claims to have been the driving force behind Sept. 11.

According to his deposition, Mohammed had been trying to persuade Al Qaeda to attempt a dramatic hijacking operation since the early 1990s. Osama bin Laden always rejected him, saying the idea was impractical - until the spring of 1999, when Mohammed was summoned to an audience with Mr. bin Laden in Kandahar, Afghanistan.

"Bin Laden told Sheikh Mohammed that he now thought the idea would work, and informed him that the operation now had Al Qaeda's full support," reads the deposition.

At first, Mohammed planned a two-pronged attack. One prong would consist of aircraft used as missiles to attack targets on America's East Coast. The second would be the simultaneous explosion of other hijacked aircraft in East Asia.

Eventually, the project was simplified in the name of efficiency.

"Sheikh Mohammed thought the operation was easy," says the deposition.

But it wasn't. Or at least, it does not seem to have run completely smoothly. Some of the potential hijackers were poorly prepared, in the sense that they did not speak English and were ill-suited to clandestine planning on US soil. Potential pilots weren't picked by aptitude.

Mohammed and bin Laden "believed that learning to fly an airplane was much like learning to drive a car; it was easily accomplished with the correct instruction," says the deposition.

In the end, the plot involved 34 participants, broken down into six groups that were based on degree of knowledge of operational details.

The top group included bin Laden, Mohammed, and other top officials, as well as a little-known, mysterious figure, Abu Turab al-Urduni.

Abu Turab trained the "muscle" hijackers in Afghanistan prior to their deployment. He taught them how to disarm air marshals, how to conduct hijackings, and how to speak basic English.

"Abu Turab also had each hijacker butcher a sheep and camel with a Swiss knife to prepare them for using their knives during hijackings," says the deposition.

Obtaining US visas was a continuing problem. Mohammed would have liked more muscle hijackers on each plane, but ended up limited to a total of 15 - four for three planes, and three for the fourth plane.

The four pilots had the ultimate control over which target they would pick from a prearranged list. "Planning for the 9/11 operation was undertaken in steps, and ... the entire plan was not set from the beginning," says the deposition.

Mohammed himself learned of the impending date of the hijackings via a courier in late August 2001. He was worried about operational security, particularly because bin Laden kept publicly hinting at an upcoming attack.

Mohammed was "concerned about this lack of discretion and urged Bin Laden not to make additional comments about the plot," says the deposition.

As for Moussaoui, he was intended to serve in a second wave of hijacking attacks, Mohammed says. After the first wave, Arabs in the United States would certainly come under suspicion, thought Mohammed. Thus the second wave would need operatives from European or East Asian backgrounds.

Moussaoui had a French passport.

That sort of long-range planning, with more than one operation going at one time, was typical of Al Qaeda, according to Mohammed. But he did not anticipate what actually happened.

"Sheikh Mohammed had no idea that the damage of the first attack would be as catastrophic as it was, and he did not plan on the US responding to the attacks as fiercely as [it] did, which led to the next phase being postponed," says the deposition.