Ethics, post-September 11

(CNN) -- Randy Cohen says his mail has changed since September 11 -- and it's not just because the letters have to be steamed and irradiated to kill off anthrax.

"I started getting a lot of letters about ratting out one's neighbors," he says. People were concerned about Pakistanis or employees of the chemical industry.

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Some of that fear has worn off in recent months, but there's still dread in the air.

"I understand why people are anxious," he says.

But he hopes that anxiety has a positive influence: Getting people to vote and becoming more active in their communities, as opposed to building bunkers and fostering a new McCarthyism.

As for the mail itself, he still can't get used to it.

"It's all steamed," he says. "It's very crinkly."