The appearance of Khalid Sheik Mohammed and four other men in a military courtroom at Guantanamo Bay, Cuba, ends a nearly decade-long back and forth over how best to try the men the U.S. says helped plan, pay for and execute the Sept. 11 attacks.

Khalid Sheikh Mohammed — or KSM, as he is known — has claimed that he was the mastermind of the attacks "from A to Z." But his ties to terrorism, by his own admission, go beyond that one plot. KSM saw himself as the sun around which his network revolved.

"Everybody who was caught knew him," says Terry McDermott, the co-author of a new book called The Hunt for KSM. "Almost everybody knew of a different plot that he was putting them in," and it took years for intelligence officials to figure that out.

It wasn't until after the Sept. 11 attacks that U.S. officials realized just how central Khalid Sheikh Mohammed was to al-Qaida's plans to attack America.

McDermott said KSM built a terrorist network based on the sheer force of his personality. He gives the example of Majid Khan, a 20-something from Baltimore who met KSM in Pakistan.

"Within a week, KSM has persuaded him to kill himself at his own wedding in order to kill [former] President [Pervez] Musharraf of Pakistan," says McDermott. "Can you imagine the gall it takes to ask someone to do that?"

That 2003 plot didn't work out. While Khan did put on a suicide vest and did wait for Musharraf at a mosque, the Pakistani president never showed.

Links To Multiple Plots

KSM was seized in Pakistan in 2003, but from the early 1990s on, he had a hand in nearly every major terrorist plot targeting the U.S. Either his family was involved, or his network financed a plot, or he himself played a key role.

The examples can fill a timeline.

The 1993 World Trade Center bombing was the work of his nephew, Ramzi Yousef. The 2002 nightclub bombings in Bali, Indonesia, were partly financed by KSM. And KSM himself did some reconnaissance for a foiled 1995 plot to blow up a dozen jetliners over the Pacific. He filled more than a dozen saline solution bottles with an explosive and walked right onto the plane. When inspectors asked him why he had so much saline in his carry-on bag, he answered: "There was a sale in the Philippines."

McDermott says that after the Sept. 11 attacks, the U.S. couldn't conceive of the vast number of plots that KSM had set in motion. "They were looking for a single thing — what's next," he says. "The problem was that there was nothing next, no one thing next — there were a hundred of them."

The list of attempted attacks linked to KSM goes on.

Tracing Suspects Back To Mohammed

Back in 2003, an Ohio truck driver had been sent to attack the Brooklyn Bridge. When it became clear that the bridge was too difficult a target, the suspect contacted the person who had sent him. Authorities traced that communication to none other than Khalid Sheikh Mohammed.

"The information went right back to Khalid Sheikh Mohammed," says Mitch Silber, the author of The Al-Qaeda Factor and intelligence chief at the New York Police Department. "Khalid Sheikh Mohammed was a very hands-on manager."

Even nearly a decade after his arrest, KSM's name is still turning up. Just last month, during a terrorism trial in Brooklyn, one of the people the prosecution called was a shoe bomber.

But it wasn't Richard Reid, the hapless British man who couldn't ignite explosives in his shoes. It was a second man who was supposed to blow up another airplane as part of a simultaneous mission.

KSM brought the two men, and the plot, together.

"In fact, KSM gave him the final orders," says Silber. "He and Richard Reid — the last person they saw from al-Qaida before they left the [Afghanistan-Pakistan] region was Khalid Sheikh Mohammed."

The arraignment of KSM and the four other Sept. 11 defendants comes just days after the anniversary of the death of al-Qaida leader Osama bin Laden.

Many U.S. officials argue that bin Laden's group couldn't have done what it did without Khalid Sheikh Mohammed. He was the man at the center of it all whose family, financing and creativity sparked more than a decade of violence.

What will emerge in the courtroom however, is a man who, after nine years in custody, has largely lost his relevance.

"I think 10 years ago his trial might have had some impact, but not now," says Phil Mudd, a former top counterterrorism official with the FBI and CIA. "I am sure people in the jihadi blogosphere will get out and talk about it, but I don't think it will have much of a ripple effect on the people al-Qaida wants to recruit. They have just lost too much traction."

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