The sentencing trial of Zacarias Moussaoui was supposed to have been the government's best opportunity to hold someone accountable for the deaths on Sept. 11, 2001. But after federal prosecutors finished laying out their case this week, even those who strongly supported an aggressive prosecution may wonder whether the trial has shed as much light on Mr. Moussaoui's culpability as it has on the missteps and mistakes by law enforcement agencies. The testimony of two prosecution witnesses, in particular, has brought renewed and unwelcome attention to how the [FBI] dealt with early warning signs. Mr. Moussaoui is the sole person to go to trial in an American courtroom for the attacks. Under cross-examination...Mr. Samit acknowledged that after the attacks he had written strongly worded reports saying his superiors had improperly blocked his efforts to investigate Mr. Moussaoui. He added that he was convinced that Mr. Moussaoui was a terrorist involved in an imminent hijacking plot. He offered a devastating comment from a supervisor who said pressing too hard to obtain a warrant for Mr. Moussaoui would hurt his career. Mr. Samit also wrote that his superiors did not act because they were guilty of criminal negligence" and they were gambling that Mr. Moussaoui had little to offer. The lost wager, Mr. Samit said, was paid in many lives.

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