About a month ago I did something very painful. I got in my car and drove to a local movie theater to see "United 93."

There are those who believe that Hollywood should not make movies about 9/11. They believe that the events of that terrible day are still too fresh, the wound is still too raw. It's even been reported that some audiences who were attending another film responded to a promotional trailer for "United 93" by yelling "Too soon!" at the screen. But it's not too soon. And here's why.

Watching "United 93" is a gut-wrenching experience. The film is shot in a documentary style that makes you feel like you are observing the action in real time. It's as if you were that proverbial fly on the wall inside the various air traffic control centers and the doomed flight itself on 9/11.

Director and writer Paul Greengrass has approached the topic without any of the frills that you expect from a major motion picture. There are no stars in the cast of "United 93." There's no George Clooney or Jessica Alba eye candy to entertain you. There's no subplot to distract you. There's no romantic interest. And there's no comic relief. All that's presented on the screen is the brutal truth of what likely happened on United Flight 93 as passengers prepared to board, boarded, waited for takeoff, were hijacked, and made the bold decision to fight back.

I say "likely," because some of what is presented in the movie is conjecture. There are things we know for sure that happened on United 93, things we can piece together from what is known, and things we will never know. But Greengrass' script is plausible and rings with authenticity, so much so that the film leaves the audience speechless and many people who have seen it have left the theater sobbing.

I guess you're wondering why I'm devoting this space to a movie that has long left the theaters. I'll tell you why. I believe that every adult American should watch "United 93." I believe that in all the rancor over party politics and the Iraq War that some of us have forgotten the truth of Sept. 11, 2001.

Many Americans have failed to learn the real message of that day. We were not attacked by a small band of zealots with box cutters but an ideology that still thrives in the world and must be defeated before there can be peace.

"United 93" doesn't shy away from showing the vicious nature of our enemy. It depicts what you know to be true. The hijackers of Flight 93 were fully aware of the pain they were going to cause, and they didn't have any remorse. They were evil.

But I can't convince most of the people I know to go see the movie. They don't want to see something so ugly and so disturbing. They want to forget. And the only way to get them to face the truth would be to pry their eyes open and make them watch like the hooligan undergoing aversion therapy in Stanley Kubrick's "A Clockwork Orange."

Lt. Col. Dave Grossman, who we interview in this issue of Police, likes to refer to the public of modern industrial democracies as "sheep." They happily go about their lives grazing, unaware of the wolves that want to devour them. And the only thing that stands between the sheep and destruction are the sheepdogs:  soldiers, cops, and others who keep us safe.

God bless all of you "sheepdogs" and the work that you do.

Still, I can't help thinking that if more people had gone to see "United 93" and relived the horrors of 9/11, it would make your jobs a lot easier. For the message of the movie is quite clear: There is evil in the world. It means us harm. And the only way to stop it is to fight back.