If nothing else, the bizarre trial of Zacarias Moussaoui - the only person in the US charged in connection with the attacks of Sept. 11, 2001 - may have highlighted the difficulties of trying suspected terrorists in established civilian courts.
Mr. Moussaoui himself has been erratic and belligerent. He has filed rambling letters with the court railing against US policies and castigating all manner of public figures, at times inaccurately. For instance, he once referred to ex-Attorney General John Ashcroft, a Republican, as "the Democratic jerk."
The case has also raised serious legal issues, notably the degree to which an accused terrorist can have access to the testimony of other imprisoned terrorist suspects.
Now Moussaoui is scheduled to stand up Friday in open court in Arlington, Va., where he is expected to (again) plead guilty. Judge Leonie Brinkema has ruled that he is mentally competent to make such a plea, and if he does in fact do so he could be sentenced to death.
Yet the nature of his ties to the Sept. 11 hijackers may remain unresolved. It is possible that "everyone has come to the conclusion, including the judge, that there is no good way to get rid of this case," says Juliette Kayyem, a homeland security and law-enforcement specialist at Harvard University.
No one holds that Moussaoui is an innocent. A French national of Moroccan descent, he was arrested in Minnesota in August 2001 after instructors at the flight school he was attending became suspicious of his behavior.
He has said in open court that he is a member of Al Qaeda and follower of Osama bin Laden, but until now he has denied any knowledge of the 9/11 plot. The federal indictment filed against him in December 2001 accuses him of conspiracy to commit acts of terrorism and aircraft piracy, among other things.
Some officials believe him to be the so-called "20th hijacker," someone who was supposed to take part in Sept. 11 but was prevented from doing so by his arrest. Yet other officials, and some outside experts, point out that the public evidence on this point is mixed.
According to the report of the Sept. 11 commission, Khaled Sheikh Mohammed, alleged mastermind of the plot, has denied that Moussaoui was part of the 9/11 team. He was slated to participate in follow-up attacks at a later date, according to Mr. Mohammed, who was captured March 1, 2003, in Pakistan.
But Ramzi Binalshibh, another alleged Sept. 11 plotter, said that he assumed Moussaoui was indeed supposed to be a 9/11 pilot, according to the commission report. He claims Khalid Sheikh Mohammed told him as much.
The commission report concludes that at the least an all-out FBI investigation of the unreliable Moussaoui conceivably might have foiled the 9/11 attacks.
"Moussaoui can be seen as an Al Qaeda mistake and a missed opportunity," says the commission report.
If his past behavior is any guide, it is possible that Moussaoui will not go through with his proffered guilty plea. He has retracted past statements made in open court. In fact, it is also possible that his agreement to plead guilty is part of a plan to raise a defense concerning his mental stability. Or years of confinement and uncertainty may have finally caused him to crack.
"I don't think any of us outside the courtroom have any idea about the weird conditions associated with this trial," says Andrew Hess, a Middle East expert at Tufts University's Fletcher School in Medford, Mass.
The trial has been delayed three times. Last month, the Supreme Court declined to review an appeals court ruling denying Moussaoui direct access to three Al Qaeda witnesses, in custody elsewhere, who he has said might back his previous contention that he had nothing to do with 9/11.
THE compromise struck by the courts allows public disclosure of unclassified summaries of statements by these prisoners. Balancing the demands of defense and prosecution in crafting these statements might have been an onerous task for US District Judge Brinkema. But if another terror suspect is ever charged in US courts, this core issue - the rights of the defendant vs. the government's need for secrecy - will surely come up again.
"If the government is going to prosecute in these courts, the courts are going to treat [accused terrorists] as normal criminal defendants," says Ms. Kayyem.
Yet to this point there have been no such prosecutions. The trial of Moussaoui remains an anomaly.
For all the billions spent on investigations into the events of Sept. 11, one might reasonably have expected more results, says Mr. Hess. While Germany, and now Spain, have put accused terrorist logisticians and other figures in the dock for alleged crimes related to 9/11, the nation where they occurred has only Moussaoui to show for its efforts.
Khalid Sheikh Mohammad and others may be in custody, but will their interrogations ever end, and will they publicly answer for their alleged involvement in the Sept. 11 tragedy? "It's a matter of concern for me, and for most Americans, I think, that we don't have more people being tried for this particular crime," says Hess.