A few lessons were buried in the rubble of the World Trade Center. Humans change the environment -- and build environments -- in ways that make them vulnerable to catastrophe. The immediate cause might be terrorists -- but could as easily be floods, lightning, tornadoes, "accident," or faulty construction. The result could be the same.

At a time like this, journalists have enormous responsibility. We want neither to advertise vulnerabilities to terrorists nor to scare the public needlessly. Nonetheless, neither public nor government can effectively protect against these threats without full awareness of them and responsible public concern.