Richard Hamilton: Altered images

Richard Hamilton's manipulations of news photographs show just how tricky taking a moral stance in art can be, says Tom Lubbock

I've always liked the Portrait of Hugh Gaitskell as a Famous Monster of Filmland. Great name, funny face, and the image has a nice collage-feeling, half fracture, half fusion, though it's not really a collage, it's a newsprint photo that's been partly painted over, human features with a mad-eyed monster mask imposed. I liked it long before I knew who Gaitskell was, or why he should be cast as a sci-fi monster. In fact he was the Labour leader around 1960, never PM, who betrayed the left by adopting a nuclear defence policy; so he was a moral monster, and the sci-fi connotations kind of fit in with the atom bomb. Kind of.

But it was and still is a funny picture. Knowing what it's about, and then looking at it, you can't feel that it's very horrified or very angry. There's the politician's prim little pursed mouth, peeping under the horror overlay. He looks more absurd than wicked. It often happens with collage that the effect turns out to be incongruity, not incrimination. This picture might be saying: what a weakling Gaitskell is, simply not up to mastering something big like nuclear weapons. But then the monster bit is rather comic too. With political pictures it can be hard to keep the message straight. I'm not sure that Richard Hamilton even wants to.

Portrait of Hugh... (1964) is the earliest picture in Modern Moral Matters at the Serpentine Gallery. It's a selective survey of Hamilton's whole career, and it's a good title, echoing Hogarth's "modern moral subjects" (A Rake's Progress, Marriage à-la-Mode, etc.). But you wouldn't call the focus exactly moral; more political. This is a series of images that deal with contemporary public agonies. You'll find works about Mick Jagger's drugs bust, the anti-Vietnam war demo where a student was shot dead, Ulster, Thatcherism, the first Iraq war, Blair's wars, Israel-Palestine, Mordechai Vanunu (he had spilled Israel's nuclear beans and was kidnapped by Mossad).

Those are the matters. But Hamilton never addresses such headline subjects head-on – as if an artist could simply pick up his brush, and paint the Ulster conflicts straight, from imagination or from life. Hamilton is very aware that, unless we're its immediate participants, we experience modern history photographically. All these matters come to us through other media, via newsprint and TV screen, before art can get its hands on them. He doesn't think that we can imagine ourselves back through these images, to the reality behind them. We can only put ourselves at a further remove, sceptically making images-of-images. The result is a body of highly self-conscious works. They're never again so funny.

In the series called Swingeing London, you see the strategy clearly at work. The same photo of Jagger and the art dealer Robert Fraser, arrested and hand-cuffed and flash-lit in the back of a police car, is its basis. It appears over and over, in various versions, colourings, mixed media, sometimes with glinting metalwork attached to the cuffs. The subject is a double capturing, by cops, by camera. Unfortunately none of Hamilton's added emphases persuades you that the image at the heart of it is especially iconic.

Of course, back then his art had news to bring. Today, the fact that our world is viewed through the mass media is no longer such news. (Incidentally, what's the alternative? Were the prints that transmitted the Peterloo Massacre such an undistorting lens?) But after you've scanned 14 variations on the same colour TV shot of the fallen student in Kent State, the effect is like a word that loses its sense through repetition: the killing turns into an abstract of petrol hues, and Hamilton's media consciousness becomes another name for indifference.

All right, I know political art gets it all ways. It's in a dilemma. People like art to be subtle. But people have rather straightforward feelings about politics – pro-this, anti-that – and they're reluctant to surrender those passions. So if art takes a similarly straightforward attitude, it gets called crude propaganda. But if it takes a more detached, above-the-fray attitude, it's called a cop-out – why not just get to the point?

Actually, both modes of art can be very good. Peter Kennard's montage, Photo-Op, showing Blair gleefully taking a snap of himself on a mobile while behind him the world explodes, is undoubtedly propaganda, brilliantly so, and very much more powerful than Hamilton's Shock and Awe, which shows Blair in a cowboy costume, again in front of a burning world. Kennard's neat splice of two images has an inescapable grip on its victim; Hamilton's over-elaborately photo-shopped image seems to be forcing its case. And the fact is that propaganda is not Hamilton's forte, however cross he may be.

But the kind of art that holds public emotions in suspension, without taking any obvious sides, is valuable too – and much harder to do. It can certainly go badly wrong. A prime case would be Marcus Harvey's Myra, shown at Sensation, in which the famous mug-shot of Myra Hindley was rendered, huge, in children's hand-prints. Harvey was working in Hamilton vein here, taking a highly charged current-affairs image, and transforming it in paint. I think he was trying to do something creditable – to dissolve this icon of outrage, and to release our minds from its awful false meaningless spell. The picture went wrong because it really didn't think how children's hands would feel, being made to recreate a huge face of Hindley. It became an extraordinarily stupid shock effect.

Hamilton's The Citizen, the centre of his Ulster trio, is another example of that reflective political art. Its ground is again an image, the image of an Irish Republican in a Northern Ireland prison, on a "dirty protest" – that is, smearing the walls of his cell with shit. It's a shockingly revolting document, and also with a potential for heroism. But Hamilton's painting also notices that the man – bearded, bare-chested – looks a bit Jesus during his Passion; and also that the shit-smears on the wall look a bit like the work of an Abstract Expressionist painter. The image is certainly put into emotional turmoil. This aestheticisation treats the protest in a way that wouldn't please any party in the conflict.

But the trouble is, when you ask: what actually is the point of this association, between shit protest and abstract painting, there is only a very superficial visual connection, which would only appeal to a superficial arty person. The picture becomes a kind of smart-arse observation for the cognoscenti, whereas what you want from a picture like this is not sides, no, but something that takes the weight and horror and tragedy of the situation.

It is a very difficult genre. The only really successful version that I can think of from recent years is a sequence of paintings by Gerhard Richter, addressing the phenomenon of the Baader-Meinhof terror gang (Red Army Faction) in West (as it was) Germany, titled October 18, 1977, after the day on which two of them killed themselves. Painted from photos, in black-and-white, in remote lost focus, it is an austere funeral piece, filled by an inexpressible misery. It's way out of Hamilton's register, which is really comedy – as once, a long time ago now, he seemed to know.

Richard Hamilton: Modern Moral Matters, Serpentine Gallery, London W2 (020 7402 6075) 3 March to 25 April