War of the Worlds (12A)

Even after these films, War of the Worlds comes as a surprise. Based on H G Wells's much-adapted Martian-invasion nightmare, it initially looks like a straggling addition to the late-Nineties wave of millennial disaster films, or even like an attempt to top Roland Emmerich's surpassingly crass terror-from-above blockbuster Independence Day.

But War of the Worlds reworks these films' themes for the post-September 11th era. In Fifties science-fiction cinema (Wells's story was famously filmed in 1953), space invaders invariably stood for the spectre of Communism - so is Spielberg metaphorically invoking another terror from the East? Well, yes, and then perhaps no. The film certainly dramatises the defensive anxiety of Bush's America, but not in ways you might expect. It has nothing of the brash triumphalism of Independence Day - don't expect to see Tom Cruise whupping alien ass.

From the start, the register is downbeat and surprisingly everyday. In a strikingly eerie, slow build-up, Ray Ferrier (Cruise), a divorced New York dock worker, collects his children - young Rachel (Dakota Fanning) and teenage Robbie (Justin Chatwin) - from his ex-wife (Miranda Otto).

No sooner are they uneasily settled in Ray's rundown New Jersey home than strange things happen: the TV reports freak lightning, the electricity fails, the skies churn with dark clouds. There's a masterfully ominous moment of stillness, nothing audible but dogs barking in the distance - then Spielberg pulls his first dramatic coup. A giant three-legged alien war machine bursts out of the street, shattering concrete and splitting buildings, before firing into the fleeing crowd.

Far from offering escapist fantasy, the film's tone is of startling, even gruelling realism. Especially when the tripods first appear, the grainy textures, drab light and hand-held camerawork create a quasi-documentary urgency that does for sci-fi what Spielberg and his director of photography Janusz Kaminski did for the war film in Saving Private Ryan.

When the Ferriers flee, Spielberg toys with the science-fiction convention of the chosen survivors - miraculously, they seem to have the only functioning car in America. But then they are practically lynched by people trying to get hold of the car. Any reassuring idea of neighbourly co-operation is mercilessly shattered; people are not merely struggling but competing to survive. Nor is there any sense of authorities in control - a detachment of Army trucks rolls past, ignoring the family as they stand helplessly by a roadside.

Humanity is hardly exalted: people are ant-like masses, mown down indiscriminately. In a sequence that is Spielberg's own mini-Titanic, people stampede to climb aboard a ferry, which is then capsized by the alien tripods. Nor are any heroes singled out to redeem human nature: Cruise's Ray is no noble patriarch, but an imperfect man blindly following his protective instincts under fire. In fact, when it comes to heroism, it's not Ray but his son who comes good - although this looks as much like self-destructive bravado as courage.

Despite the imposing effects, this is a film less about spectacle than about human behaviour. One of its most sobering moments, with Cruise, Fanning and an excessively wild-eyed Tim Robbins trapped in a basement, shows how far Ray will go to protect himself and his daughter. The picture of social breakdown comes unnervingly close to the zombie films of George Romero, who might well have imagined the poetically bleak image of Rachel standing by a river watching corpses float by. The mounting sense of desolation also echoes Hitchcock's The Birds, with humans outranked by an enemy totally hostile and totally alien.

This is a disaster film that in no way flatters America - which is no doubt one reason why Paramount surrounded it with such zealous secrecy before release. It's not impossible, however, to produce a "patriotic" reading of War of the Worlds as a film about what could happen if America let its guard down against the ruthless Other. That could easily be construed as the meaning of Morgan Freeman's opening voice-over quotation from Wells, evoking humans going about their business "with infinite complacency" while "intellects vast and cool and unsympathetic regarded this earth with envious eyes..." - the last two words echoing the classic Bush explanation of Middle Eastern resentment.

Yet that interpretation simply isn't borne out by the experience of watching the film. Besides, that Ray's children ask whether terrorists are attacking suggests an over-obviousness that should really send us looking in another direction. In fact, this is a film that aims to evoke as concretely as possible what it might be like to live through an invasion by unforgiving powers - to live, for example, in Iraq during the American invasion. It's a reading that has been confirmed by screenwriter David Koepp, and a giveaway clue is that Robbie's homework project is on the French occupation of Algeria.

War of the Worlds is seriously compromised by an ending that comes across as abrupt and derisory, although it's actually true to Wells's novel. I prefer to think that, just like AI, the film "really" ends some 20 minutes earlier, on a much grimmer note. Either way, War of the Worlds is not the sci-fi epic you might be expecting - but it's definitely one of those films that Steven Spielberg makes every few years to remind us that he's a far more interesting director than the benign theme-park humanist we tend to imagine.

j.romney@independent.co.uk