The videotape found of Las Vegas landmarks, originally thought to be a terrorist “casing” video, might have been simply a tourist’s keepsake. An audiotape thought to contain an anti-American hate speech appeared to be just an old children’s song in Arabic about a duck.

And the odd sketch in a day planner of what looked like a blueprint for an attack on a Turkish air base? Perhaps nothing more than a mentally ill man’s doodling of a Middle East map, prosecutors were forced to acknowledge.

Prosecutors turned against prosecutors. Ethics inquiries were opened and criminal charges filed — this time against two government officials who helped put the case together. Attorney General Ashcroft was reprimanded by the judge in the case for falsely linking the suspects to the Sep. 11 attacks in violation of a gag order.

There were no clear winners in the case; a certain loser was the federal government itself, as its “new paradigm” of thwarting terrorists before they struck clashed headlong into age-old notions of justice and due process.

As a reporter in Washington covering terrorism, I was always fascinated by the Detroit case and what it said about the country’s shifting attitudes toward terrorism after the attacks on the World Trade Center and the Pentagon.

In the immediate aftermath of the Sept. 11 attacks, the fear that gripped Washington over “second-wave” attacks was overwhelming. The near-certainty of another attack was an article of faith among Bush administration officials.

We in the media breathlessly covered every warning and tip about threats real and imagined: scuba divers, cargo trucks, tourist helicopters around the Statue of Liberty, a cable-cutting blowtorch on the Brooklyn Bridge and more, as if they were the next big attack. The F.B.I. and the C.I.A. had failed to connect the dots before the 9/11 attacks, and the country was determined not to let that happen again.