Could It Happen Again?

A bipartisan inquiry into 9/11 finds intelligence failures that might have been avoided. Two years later, what has been fixed and what is still broken?

Paul Fusco / Magnum Photos

Union Square, September 14, 2001
People gather for a candlelight vigil.

Looking back on it now, it is difficult to choose the precise moment when U.S. government officials--hobbled by old-fashioned rules, saddled with ancient computers that could not talk to one another and riven by silly bureaucratic rivalries--missed their best chance to thwart the plot by 19 hijackers to take over four airplanes, turn them into flying missiles and kill almost 3,000 people nearly two years ago.

Was it in early 1999, when the National Security Agency, eavesdropping on a suspected terrorist facility in the Middle East, first learned (but kept to itself) that a 25-year-old Saudi named Nawaf Alhazmi had links...