Lost: 'UNITED 93'.

United 93, Paul Greengrass's depiction of the 9/11 jetliner whose passengers rose up against its hijackers and crashed it into a field in Pennsylvania, is a movie less interesting in itself than in the questions of intention and reception that surround it. Why do we need a movie like this? One asks this all the time about bad movies, of course; but United 93 is not a bad movie, and so the question isn't merely rhetorical. What is the point of depicting an event already as enormous in the public mind as the attacks of 9/11?

The film carries with it an unsettling sense of sacred memory and the lurking potential for blasphemy. Standing in line for tickets, a friend and I discussed flight-disaster movies, and as we laughed to recall the inane comedy of Airplane, suddenly I worried: might someone within earshot be offended? Such wariness surely in part explains the near-unanimous praise United 93 has received from reviewers. Who wants to desecrate a national shrine? I understand that the first screenings in Manhattan were attended by family members. You couldn't have paid me to go.

As for the actual film, it is understated and scrupulous, anxious to distance itself from the dazzling action of the director's last film, The Bourne Supremacy. Here Greengrass uses unknown actors, as if to avoid exploiting the material or tainting it with celebrity. The film opens on a note of somber restraint--no music, just a black screen and a deep, faint drumbeat of dread. Given this decorous tone, it's disconcerting to encounter, in the movie's opening scenes, the tried-and-true formula of the air-disaster genre. It's all there. Stewardesses chat about their love lives as they stock the galley kitchen. Pilots discuss family trips as they run through equipment checks in the cockpit. Passengers stream in from their disparate lives to the waiting area, oblivious to the sword of Damocles hanging over their heads. There's even the guy-who's-late, the tragic last passenger squeezing in as the crew is closing the door. "You just made it!" says the stewardess with a bright smile.

The guilty pleasure of disaster movies lies in being present at the first, small, dawning awareness that something is terribly wrong, whether towering infernos (first whiff of smoke) or death-dealing twisters (ominous green hue in the sky)--or the errant blip on a flight controller's screen that signals mayhem appearing, as it were, out of a clear blue sky. As a nervous flyer, I've always particularly enjoyed airplane disaster movies, from the Airport series of the 1970s through more recent examples such as Con Air and Executive Decision. Assembled out of schlocky cliches, peddling vicarious terror and a cheesy catharsis, they are the fluffiest of cinematic treats.

The trick United 93 plays is to situate us in this familiar form of entertainment and then not let us be entertained--to dangle the cotton candy and then yank it away, plunging us from cinematic fun into dreadful commemoration. Those clear blue skies are no metaphor, after all, but the actual skies of a day whose trauma we remember all too well. There is something covertly cruel in this. For instance, take the sequence intercutting frantic action in the flight-control room with the tedium inside Flight 93, delayed on the runway, inching forward in a long line of planes waiting for take-off. The terrorists exchange nervous glances. Will the pilots get the news of other hijacked planes in time for Flight 93 to be aborted? Again, it's standard dramatic device. But we can't respond in the standard moviegoer's way.

Greengrass keeps things focused closely on the action in the plane and in the various control towers; virtually the entire movie takes place in these two cramped and claustrophobic environments. He keeps us in the pressure cooker. We feel the terror of passengers as the nightmare of hijacking deepens into the worse nightmare of a suicide mission. We feel the frenzied confusion on the ground, as air controllers and military officers struggle--with 4,200 commercial jetliners in the skies above America--to figure out what is happening and what they can do about it, handcuffed by colossal bureaucracies with unclear lines of authority, and by a default belief, even among the military, that this can't really be happening ("Is this a sim?" "No, it's real world!"). As the images of destruction in lower Manhattan make their way onto various TV screens, Greengrass evokes the emotions of the day: stunned disbelief, mouth-gaping horror, and amazement. We feel that, too.

All this feeling amounts, I suppose, to a kind of catharsis. You go to United 93 expecting to be put through the wringer, and the film does not disappoint. It is as full of emotional content as it is empty of political. Much has been made of Greengrass's success in treating the terrible events of that day with respect, and there's a relieved impression that he has no axe to grind--unlike, say, Oliver Stone, whose film on 9/11, due out in August, is already eliciting trepidation. But an obligation to "respect" is an odd challenge for a filmmaker, and a severely limiting one. What finally is United 93? A documentary without real truths to uncover. A feature film without featured actors. A work of art with the art left out.

What remains is a faithful stab at what you might have experienced if you'd been there on that day. But this "there" is already familiar to us; the movie merely deepens what we've already seen countless times on TV. I found myself longing for a novelist's willingness to do the opposite, to take the familiar and make it strange. With its powers of interiority, its fleshed-out characters and digressing narrators, imaginative literature can hardly limit itself to "respect." Consider, for instance, Martin Amis's recent New Yorker story, placing at its center a Muhammad Atta who--here is Martin's "take"--has no particular religious belief or political animus, but rather one very general animus: he hates life itself, its messiness and physicality, its sensual appetites; and since America is the world's prime source of sprawling, creative, greedy energy, it is America he must slay. Amis's narrative of the ultimate death trip reminds us that what we need in the face of something like 9/11 is not neutrality, but precisely the opposite: a version of events; an interpretation.

Back then to the original question. Why do we need a film like United 93? My guess is that the answer lies in the power movies have to make things real--even, strangely enough, the things that already are real. I recall, years ago, a friend telling me that he'd seen his old Staten Island neighborhood in a passing shot in a movie, and that it filled him with an almost vertiginous sense of where he had come from. Perhaps this mysterious validation is what we seek in United 93--simply seeing ourselves, in the largest collective sense possible; seeing ourselves in that moment when calamity turned our country into a neighborhood.

In its opening scenes, United 93 contrasts the focused and intense ritual of the three terrorists, praying in a hotel room before their mission of death, with the relaxed and aimless morning everyone else is having, including passengers talking on cellphones--cellphones which, we know, will soon be converted to machines of dire urgency. Greengrass doesn't wrap these scenes in poignancy, he just puts them there and lets us appreciate them for their very inconsequentiality: to me they are more moving than the scenes of desperate heroism to come. They remind us of when mass political violence--specifically, being on the receiving end of it--was the farthest thing from our minds, and we lived with an innocence we may never have deserved, but cherished nonetheless.

Barry Ackroyd's handheld camera evokes reality TV, but the graininess of some of its images, and now and then a faux-inadvertent blurring of focus, suggests home movies as well. That is apt. These vignettes of nothing in particular come to us from a time that seems longer ago than it can possibly be. They remind us how lucky we were to be able to be bored in airports. They are the home movie of a collective childhood we will never have again. Leave it to novelists to tell us why.