Why is a psychologist writing about post-9/11 America?

I'd been watching people accepting things after 9/11 that a few months before they would never have accepted, saying things they would never have said.

Like the 2004 incident in which the singer Yusuf Islam--Cat Stevens--was arrested on a plane.

The thing that struck me was the knee-jerk reaction of people to not just believe that he was guilty, but to be uninhibited about saying racial things. And one day it occurred to me: We are all just scared to death. It's like somebody turned a switch.

The paranoia switch?

Yes.

Which means what?

It means what happens in our brain when we get traumatized and memory traces in our brain fire off later--like the soldier who drops to the ground when he hears a car backfire. That pushes the paranoia switch in his brain. It's also the term I use to refer to what happened to all of us on 9/11. We were switched from our normal mental state to one of paranoia and anxiety.

You argue that six years later we're still traumatized. Why?

Fear will generally abate with time if the source of the trauma doesn't recur. In this case, we didn't have another large terrorist attack in this country, but we were constantly reminded of how frightened we should be.

You criticize "merchants of fear" who exploit terror for political gain.

All that any politician has to do is just whisper the notion of revenge, and we'll be right there.

You're talking about President Bush.

We shouldn't restrict the discussion to particular names. The problem has a particular name in the year 2007. It had a different name in 1950, and will probably have another name in the future.

Yes, you compare the post-9/11 era to the World War II internment of Japanese-Americans and the McCarthy years. Haven't we learned anything?

I'm optimistic enough to hope that we've done better than in World War II or the McCarthy era. But I'm going to reserve judgment.

Will we one day admit that fear was driving many of our public decisions?

We're much likelier to admit that certain things were wrong than to admit that we did them because of fear. People don't want to admit being afraid. Why not? What's so bad about fear?

Just for the sake of the argument, let's say that we got ourselves into a horrible war based almost solely on the fact that we were afraid. If you admit that, you not only have to admit that you were afraid, which is hard enough, but that you were culpable in killing thousands and thousands of people.

So what's the solution?

In the short term, I hope that when there's a shift in leadership, people can be helped to understand how infinitesimal the individual threat of terrorism really is, so that they can feel calmer and less aggressive.

And in the long term?

I hope that people can understand that fear itself is worse than just about anything we can be afraid of.