WASHINGTON — Zacarias Moussaoui, the only person prosecuted in connection with the worst terrorist attack in American history, did not get the death penalty because some jurors concluded that he had little to do with Sept. 11.
Yet two presumed key planners of the Al Qaeda plot, Khalid Shaikh Mohammed and Ramzi Binalshibh, have not been charged, though they have been in U.S. custody for more than three years.
A central contradiction in the Bush administration's fight against terrorism is that bit players often have been put on trial, while those thought to have orchestrated the plots have been held in secret for questioning.
The difference in treatment, government officials say, stems from the view that gathering intelligence from suspected terrorists is more important than publicly punishing them.
That's why Muslim men from Portland, Ore., Lackawanna, N.Y., and Lodi, Calif., have been prosecuted and imprisoned for having attended training camps in Afghanistan or entering the country intending to do so. Facing charges such as conspiracy and providing "material support" to terrorists, they had little of substance to reveal to U.S. intelligence authorities.
Similarly, the Bush administration sought life in prison for John Walker Lindh, the California-born Muslim convert who went to Afghanistan to fight for the Taliban government prior to the U.S. invasion in late 2001. He pleaded guilty in exchange for a 20-year sentence.
But it was a different matter when the FBI arrested Jose Padilla in Chicago in 2002. The Brooklyn native, a convert to Islam, was suspected of leading a plot to set off a radioactive "dirty bomb" in the United States.
Rather than file terrorism charges against him, the government branded him an "enemy combatant" and confined him to a military brig for three years. He was not allowed to speak to his family or to a lawyer while interrogators pumped him for information about the supposed plot.
Government lawyers said they were reluctant to charge Padilla with a crime, because that would entitle him to a lawyer. And a lawyer undoubtedly would tell him not to talk to government investigators.
Late last year, after Padilla had legal representation and as the Supreme Court was deciding whether to hear his challenge to President Bush's assertion of power to detain without due process Americans deemed to be enemy combatants, the administration changed course. He was charged with several minor terrorism-related crimes, but not with plotting to set off a dirty bomb.
Though the Moussaoui jury seemed to indicate that he had not been directly responsible for the Sept. 11 attacks, Mohammed has told investigators about the plot in great detail.
According to reports of Mohammed's statements during interrogations, 10 years ago he conceived of the idea of using hijacked airplanes as missile-like weapons, and eventually persuaded Al Qaeda leader Osama bin Laden to fund the plot.
Originally, Mohammed wanted to hijack 10 planes and fly them into five targets on the West Coast and five on East Coast. Bin Laden thought this was too complicated, and they agreed to concentrate the attacks on the East Coast.
With that settled, Mohammed was put in charge of the plot against New York and Washington.
He said he chose Binalshibh to coordinate the operation of the 19 hijackers and to serve as their paymaster. Both men were captured in Pakistan -- Binalshibh in September 2002 and Mohammed six months later -- and are being held in secret prisons outside the United States.
In a 56-page statement submitted as evidence at Moussaoui's trial, Mohammed stressed that Moussaoui was seen by leaders of the Sept. 11 plot as unreliable. Moussaoui was to train in the U.S. and be ready for a possible "second wave" of attacks, Mohammed said.
Moussaoui "did not know [Mohamed] Atta," the leader of the hijackers, "and there was never any contact between them," Mohammed said.
That did not prevent the administration from prosecuting Moussaoui, who had been arrested in Minnesota and jailed on a visa violation three weeks before Sept. 11, 2001. He pleaded guilty to being a part of the conspiracy, and the jury Wednesday sentenced him to life in prison without parole.
Administration officials said recently that it was still possible that Mohammed and Binalshibh would be prosecuted.
"With every case, the government has to make a calculation. There are pros and cons. It involves weighing how much information would be released in court," said one official who insisted on anonymity because he was not authorized to discuss the process.
If the Supreme Court upholds the U.S. military tribunals for terrorism suspects being held at Guantanamo Bay, Cuba, the administration could try high-ranking Al Qaeda leaders there.