ART / The Kitaj myth: 'The man who would leapfrog his way into History on the backs of giants stands exposed.' Andrew Graham-Dixon on Kitaj at the Tate

R B Kitaj, a man well versed in the literature of Western Europe, is doubtless familiar with the old French expression 'Il ne se prend pas pour de la merde', which may be literally if a little clumsily translated as 'He does not take himself for a piece of excrement'. Kitaj, for one, most certainly does not. The absolute assurance with which he views himself as an artist of world-historical significance lends his exhibition at the Tate Gallery a poignancy which his paintings themselves, so cold-hearted, never begin to achieve. 'R B Kitaj: A Retrospective' presents the dispiriting, admonitory spectacle of an oeuvre ruined by fatal self-delusion.

The myth that Kitaj has so painstakingly constructed around his life and work has seduced many into believing that he is a considerable painter. The Kitaj of Kitaj's legend is a turbulent intellectual in permanent geographical exile from his native country, America, and in permanent emotional exile from the broader modern culture which he disconsolately occupies. A Wandering Jew for the 20th century, this mythical Kitaj is the visual poet of diaspora and the style of his art, with its broken, discontinuous surfaces, its enigmatic elisions of unlike subject matters, reflects nothing less than the vagaries of the Human Condition itself.

'The paradigm of Kitaj's art,' according to one of the more breathless believers in Kitaj's myth, 'is Eliot's Wasteland.' According to Kitaj himself, an inveterate name-dropper who claims Muse-like inspiration from a quite remarkable number of major writers and painters ranging from Kafka to Matisse, Jean-Jaques Rousseau to Walter Benjamin, 'I'd like to try, not only to do Cezanne and Degas again after Surrealism, but after Auschwitz, the Gulag.' Dangerous talk: there are paintings by Cezanne and Degas on view in the Tate.

Kitaj's habitual reluctance to allow his paintings to speak for themselves means that almost every work is displayed alongside a long and usually unenlightening footnote to its effects and meanings, supplied by the artist himself. The text which accompanies The Rise of Fascism, a less than memorable pastel of three women and a black cat by the sea, is both exemplary and short enough to quote: 'The bather on the left is the beautiful victim, the figure of Fascism is in the middle and the seated bather is everyone else. The black cat is bad luck and the bomber coming over the water is hope.' This may be intended ironically, a way of remarking how difficult it is to treat the large themes of history without descending to banal, trite symbolism. But Kitaj's painting is, elsewhere, so often banal in ways that cannot possibly be intentional that the suspicion lurks that here, too, he is in deadly earnest.

Kitaj's art is constantly collapsing under the enormous weight of its creator's ambitions for it. The Ohio Gang, 1964, is an early and prophetic instance of this. Its theme is the theme of so many of Kitaj's paintings, The World Gone Mad, and the cluttered, collage-like disposition of figures within its perspectiveless space is transparently intended to serve as a metaphor for this. A kinkily dressed matron and a pair of abbreviated interrogators clearly have evil designs on a naked girl, one of the first of Kitaj's several pallid, doe-eyed victims. A homunculus in a pram is being wheeled about by a monster nanny while a faceless figure in the background ascends into a brown and black void.

The Ohio Gang may only be a piece of juvenilia, but it exemplifies the shortcomings of Kitaj's work as a whole. Its subject, the terror and misery of life in the 20th century, is enormous. But if a painter wishes to treat vast and terrible themes, he must paint vastly and terribly moving pictures, and Kitaj cannot do this. His monsters are not truly monstrous but they are, rather, cartoon cut- outs standing in for the idea of monstrousness - it is only necessary to look at the work of Goya, another of Kitaj's supposed heroes, to see the difference between truly horrific political painting and Kitaj's version of it. This show makes it very hard to believe that Kitaj's is an art that has actually been nourished by long study of the great masters.

Kitaj's gifts are those of a reasonably competent illustrator, in the sense that most of his pictures may be said to illustrate rather than embody their themes. They always remain about their subjects, which is one of the reasons why they never manage to be moving. There should - at least according to the myth of Kitaj - be a huge pressure of feeling behind his pictures. But the feeling always seems willed rather than truly present, like the emotions imperfectly summoned up by an actor playing a part without conviction. In The Autumn of Central Paris (After Walter Benjamin) Kitaj essays the ineffable melancholy of the flaneur contemplating the swift sad corruption of his culture. But, typically, none of the sadness that should be in the painting, a collage of inert figures and faces, has made it into the paint itself.

A deep sense of alienation is one of the most pronounced characteristics of the mythical Kitaj, which is probably why he has felt the need to paint pictures of brothels. He is playing, here, at being a second Degas, an unflinching painter of modern life. But there is no emotion, no tension and no animation in Kitaj's visions of sex - nor even the disturbing sense of a lack that might have been won from the absence of those things. The pictures are embarrassing, but not in the way they are meant to be: you know exactly what you are supposed to feel (the horror, the horror) but, obstinately, the feeling just will not arrive.

The larger the themes, the more acute this embarrassment. Kitaj's art, despite its many obliquenesses and opacities, is essentially an obvious art. The subject of If Not, Not (he might as well have stencilled it on to the picture) is Death Amid Beauty: the terrible contrast between the beauties of the landscape in which Auschwitz was sited and the horrors that went on there. Kitaj's solution, a candy- coloured landscape thronged with cartoon figures of the dead and the dying and the terminally miserable, is not only crass but also a staggeringly trite cheapening, in art, of human catastrophe. The flaccid, anaemic quality of this painting, the way in which it attempts to generate feeling by feeding on something so horribly beyond its own expressive reach, is extremely unpleasant.

Elsewhere, Kitaj attempts to treat the Holocaust less bombastically. In black charcoal, he draws the entrance to Drancy, where Parisian Jews once huddled before their last trips elsewhere. But even Kitaj being understated feels false and portentous and the give-away is that all his pictorial devices, in a picture which presents itself as simple, solemn observation, are cliches: the darkening cloudy sky, the bleak coal dust speckling of the picture surface, the louring black silhouettes of anonymous buildings. Other pictures in a similar vein include a series of brooding interiors which fail, precisely, because they are Brooding Interiors, Loaded With Overtones.

It is clear, fairly early on, that things will get no better. The philosopher Richard Wollheim, in an otherwise dully hagiographical essay about Kitaj, records that 'in the summer of 1992, Kitaj asked me, 'Are you familiar with that phrase 'old-age style'?' I said I was. He said that that was what he was now interested in.' In the absence of any apparent emotional drive to create pictures, Kitaj has spent his life concealing an absence, a lack in himself. His 'old-age style' is just another of his disguises and in this as so much else he is merely imitative, a painter going through the emotions but incapable of experiencing them.

The careless manner which Kitaj has lately adopted is a hybrid style of pastiche: a little bit of fake Beckmann, a little bit of fake Picasso, but above all fake. These are the paintings of someone who feels he ought to be painting like this - looseness, freedom, gestural self-expression generally being regarded as traits of great artists in their old age - not of someone compelled to paint like this. Their transparency is pitiable partly because, by painting them, Kitaj has finally allowed the myth of himself to be seen through. The Wandering Jew, the T S Eliot of painting? Kitaj turns out, instead, to be the Wizard of Oz: a small man with a megaphone held to his lips.

(Photographs omitted)