One of my college professors used to say that paranoia is merely a higher state of enlightenment.

The 9/11 atrocities changed America. But unless they were directly affected, I don't think it really changed individual Americans. In fact, I think it had the opposite effect. If you were liberal before the attack, it made you more liberal; conservative, more conservative; pacifist, more pacifist...

In my case, it cemented and magnified my belief that the world is a dangerous place. In short, it intensified my belief in vigilance that I admit sometimes borders on paranoia.

About two weeks after lower Manhattan was attacked with the Islamist version of kamikazes, I was seated in the 15th row of a commuter flight. A month earlier that flight would have been packed. But in late September 2001, it was almost empty, except for a few nervous frequent fliers.

So when a young, dark-haired woman pulled out a small digital camcorder and started to record footage of the passenger cabin, it got even more tense. In the wake of 9/11 what would have been an unusual but ultimately dismissible breach of passenger protocol, suddenly became a matter of national security.

Reports had just circulated that actor James Woods had shared a flight with some of the 9/11 terrorists in August 2001 and reported to the flight attendant that he thought the men were rehearsing a hijacking. Nothing came of Woods' report.

But it was on my mind as I watched that young woman videotape the passenger cabin. And I wasn't the only one who was concerned. Several passengers asked the flight attendant to look into what the woman was doing. The flight attendant did as we asked and the puzzled young woman put away her camcorder, wondering why her fellow passengers objected to her attempt to record her trip.

I was reminded of this little non-incident the other day after Police received a routine e-mail request for a subscription. As is my practice I forwarded that request to our circulation department, asking them to help the potential subscriber.

The e-mail response from the circ department read: "Over the last month we have received about eight to 12 requests for subscriptions to be sent to P.O. boxes in Iran."

Well...that started my spider sense tingling. Was some Jihadist group in Iran making a clumsy attempt to learn about American police tactics by reading Police magazine? It's not as laughable a concept as some of you might think. During the Cold War, Soviet agents used to spend a lot of time poring over Aviation Week & Space Technology, looking for information on the latest American military technology.

All that said, it's really unlikely that the person asking for a subscription from Iran is a terrorist. Our Iranian "friend" is probably just a cop, or some government official, or maybe a representative from that police trade show in Tehran that sent me an invite to attend. Thanks, guys. But...uh...I'll pass.

Still, he could be a bad guy, which is why the circ department has not honored his request. Does that make our circ department paranoid or vigilant?

Vigilance is a force multiplier for cops. For example, a neighborhood watch program is an example of how much a vigilant public can assist sworn officers. In contrast, the thousands and thousands of reports to the FBI in the days after 9/11 are an example of how much pain public paranoia can cause.

The problem is, you can't tell what's paranoid and what's vigilant until after the report has been investigated. So every report must be treated seriously.

Was James Woods paranoid when he reported on his fellow passengers in August 2001? Maybe. But on the morning of Sept. 11, 2001, his paranoia became a shining example of vigilance, the kind of nationwide neighborhood watch that we need to foil future terror attacks. And to paraphrase my former college professor, vigilance is a higher state of enlightenment.