Arts: Rip it up and start again?

The power of Peter Kennard's photo-montages is obvious. But is it an indignant call to action or simply impotent frenzy?

We mock it, but are there in fact any good jokes about the Millennium Dome? I mean, specifically visual jokes, about the building itself? No. Richard Rogers' design seems to have defended itself well on this front. It looks weird - but it doesn't really look like anything else. It is invulnerable to damaging visual puns.

Oh, you could maybe see it as an old sea mine breaking the surface; or the top of a sci-fi headset (the kind used for mind-swaps); or a grounded UFO. But all these associations are vague. None is the clincher that, once noticed, can never be unthought. However much we hate it, the Dome can't be convicted through its appearance. But if it could, this would be a job for photo-montage.

Peter Kennard is the leading British photo-monteur. He's been making anti-nuclear, anti-capitalist image-splices for about 30 years. His classic picture from the Seventies shows cruise missiles loaded on to Constable's haywain. Kennard has several shots at the Dome in Domesday Book, his exhibition at Gimpel Fils. (He has a book of the same name out, too.) But none of them hits as smartly as the verbal pun in the title.

Like the best puns, it's a great fluke. We have this old spelling, Domesday, meaning "doom", but saying "dome"; and then we have the Millennium Dome, plus superstitious fears that one way or another (Second Coming, Computer Bug) the world may end. Sorry to kill a joke through analysis; some jokes deserve a thorough autopsy.

Good puns also have a way of not saying what you might want them to say. And Kennard's vision in this show isn't exactly apocalyptic. What he wants to say is that the Dome is disgustingly triumphalist, a distracting side- show, when there is nothing in the world to celebrate. And in many images he takes an image of the Dome, lit up at night, and splices it with some other image - of poverty, warfare, death.

But he can't really use the Dome's shape in a damning way. In one, for instance, there's a skull, with the dome as its crown. The connection works, but it doesn't stick. You don't think: of course, the Dome, it's like the top of a skull. The pun is too imprecise. The splice lacks the undeniability, the indelibility, that is one of photo-montage's great powers. And, as I say, I think the Dome has been carefully designed to defeat all comers in this game.

Perhaps this power of photo-montage is failing anyway, another victim of the digital manipulation of photos. John Heartfield's great pun against Hitler - showing the Fuhrer's flipped-back Nazi salute as a gesture for taking back-handers from big business - strikes only if the montage uses an authentic, undeniable photo of Hitler. It makes Hitler's gesture seem to give itself away. And if you thought the image of Hitler had been altered by Heartfield, that sense would be weakened. But now, when any photo may be unnoticeably altered, photo-montage loses its undeniability effects.

Peter Kennard's art has never much depended on the perfect visual pun. Its strategies have been more symbolic. And this show continues to deploy a lot of his established vocabulary of symbolism. The bombs and missiles, the planet Earths, the skulls, the gas masks, the babies - these emblems have fuelled Kennard's imagery for a long time, and I think returns are diminishing. There's also the feeling that, while the pictures want to hate all these missiles, they rather love their dark, phallic forms, too. Or, at any rate, the pictures don't fully wish them away. The bombs are simply too much at home in Kennard's powerfully shady, filthy black-and- white aesthetic. And the tone of his art is far from the agit-prop you might expect; it's rather a resigned, obsessional, brooding pessimism.

But that isn't all. This exhibition and this book also include some of the most forceful pictures Kennard has made to date. They are images - appropriate to the medium - in which human flesh meets print and paper. And, as sometimes happens in his work, the physical impact exceeds and takes over from any clear moral agenda.

I'm thinking in particular of the images of newspaper, open at the share price pages, which are being scratched and ripped by shadowy hands. I suppose that overtly this is an image of resistance or revolt. The excluded, the human lives behind the figures materialise out of the newsprint and tear capitalism to shreds. But it becomes a very ambiguous image.

Simply, the attack appears both wild and deranged. The damage done to the newspaper is extremely violent, made with nails but looking like the work of knives, and the cuts in the paper feel like flesh wounds. But of course, physically to attack a newspaper is mad. And to attack the share price pages obviously doesn't touch the stock market itself. But then the thing about an economic system is that it is untouchable, literally ungraspable.

And then, at the same time, the shreds of slashed newspaper seem to be slashing back, cutting at the hands that tear, as if the hands were really tearing at broken glass. And the hands partly seem to be ghostly blurs, bodying out from/ dissolving into the smearing of printer's ink or again - you can't tell in black and white - it may be blood.

These are extremely visceral images, but they have a complexity that defies being worked out as a clear moral equation. Chiefly, they seem to be images of impotent frenzy, depicting fantasies of impossible destruction. Since they're partly about attacking the world through its representations, you could see them as about photo-montage itself, its desires and limitations. The montager, like the iconoclast and the defacing graffiti-artist, deals in proxy violence, attacking nothing more real than print on paper. Well, I'm not sure. But they certainly cut to the quick.

Peter Kennard: Domesday Book, Gimpel Fils, 30 Davies St, London W1. Free. Until 22 Jan. (Closed Sat pm, Sun and 23 Dec-5 Jan). `Domesday Book' (Manchester University Press pounds 40, pounds 14.99 paperback)