Look. Nobody doubts that Moussaoui, a Frenchman of Moroccan heritage, was an agent of al-Qaida. No one questions that he was in the United States for nefarious purposes. It happened -- miraculously -- that the FBI actually picked him up before 9/11, so that on the fated day, he was in jail, removed from mandibular contact with people actually tortured, burned or propelled to suicide.
But the law holds him as an accessory. Moussaoui is far from furtive about his association with the bloody jihadists. It is persuasively argued that he might not in fact have served as the 20th man on one of the killer flights because he was too unreliable. Not as to motives -- he is entirely outspoken about wishing all Americans dead, except presumably those who are sympathizers and have not been detected by the FBI. It seems to have been a question of technical unreliability, so that boss-man Mohamed Atta evidently decided to have him stay away from that day's suicide planes, perhaps to study them on television, preparing himself for future active participation.
Again, bear in mind that Moussaoui has been found guilty in a formal judicial procedure of collusive involvement in an operation designed to kill U.S. civilians. That has been done. What goes on and on is the question of an appropriate penalty.
This beggars analysis. Why is it so important to the prosecution to go to such lengths to prove that Moussaoui deserves to be executed? Damage is done by this undertaking, because if the government fails, then the aroma of the trial will waft toward an ambiguity concerning the entire business. If Moussaoui "prevails" in the Virginia trial -- if execution is not ordered by the jury -- loose-minded analysts will arrive at the conclusion that he was finally not guilty of atrocious deeds, although he has admitted that he'd happily have been a member of the suicide team if he hadn't been detained by the FBI.