Holding up handcuffed hands to cover their faces, Mick Jagger and the trendy art dealer Robert Fraser shield themselves from the flash-ing cameras. The year is 1967 and they have been arrested on a drugs charge. The two friends seem defensive. But then we realise that both of them are smirking, and the outflung hands suddenly look as if they are waving in gleeful defiance. Richard Hamilton, who produced this iconic image, called it Swingeing London, wittily highlighting its blend of irreverence and oppression. However amused Fraser may appear, he served a prison sentence at Wormwood Scrubs for possession of heroin.
If Tate Britain's "Art and the 60s" show concentrated only on the decade's frothiest aspects, it would fail to convey the reality of these complex years. But the exhibition opts instead for extreme, even bewildering, diversity. Our eyes are wrenched from David Bailey's acrobatic photo sessions with leggy, pouting models to far darker concerns.
At the start, where Anthony Caro's revolutionary abstract sculpture occupies a centre-stage position, we find ourselves confronting the Destruction in Art Symposium. It hit London in September 1966 under the canny and resolute guidance of Gustav Metzger, who had already pioneered his own acts of obliteration while wearing a gas mask. Police stopped Hermann Nitsch's ritualistic performance with an animal carcass, but nothing could prevent Yoko Ono sitting impassively on stage while her clothes were sliced off her body, piece by piece. In their dramatic and disparate ways, all the contributors to this spectacular eruption were bent on making audiences aware of "destruction in society".
Some of the most powerful images in the Tate show focus on the nuclear threat. I vividly recall listening to the sound of jets screeching over my school classroom in the early 1960s. The Cuban missile crisis was at its height, convincing me and my teenage friends that we would all be incinerated by Russia. The anxiety of that time is trenchantly conveyed by one of the least-known artists on view here. Colin Self, who had only just left the Slade School of Art, produced an extra-ordinary image called Guard Dog on a Missile Base. The animal bares its fangs, revealing a predatory, blood-red mouth. It seems as eager to attack as the state- of-the-art weapons ranged beyond, each one thrusting into the sky with cold, vengeful menace.
By including such unfamiliar work, the exhibition fights against the surprisingly widespread fallacy that the Sixties were merely frivolous, celebrity-obsessed years. Peter Blake, in a large self-portrait painted in 1961, certainly made no secret of his infatuation with rock stars. Badges festoon his blue denim jacket, and his right hand firmly clasps a fanzine with Elvis's grinning face on the cover. Yet Blake stares out at us with unexpected solemnity, studiously removed from the mass hysteria surrounding singers of the period and conscious, above all, of a strange inner melancholy.
Even the most frothy of subjects are treated with remarkable insight by some artists. True, Antony Donaldson's Take Five is nothing more than a lightweight, randy trumpeting of one young man's lust for faceless pin-ups in bikinis. He sums up the most superficial side of the show. But then there is Pauline Boty, one of the very few women artists in this male-heavy survey. Her painting The Only Blonde in the World shows Marilyn Monroe teetering on a nocturnal street flanked by brilliant, heraldic and oddly target-like illuminations. The entire image stresses Monroe's vulnerability. She looks ready to collapse.
This refusal to be seduced by the most superficial aspects of the consumerist world gave British work of the Sixties its strength. Blake always complains that he has never been properly acknowledged in America, where Roy Lichtenstein, Andy Warhol and Claes Oldenburg swiftly became the international superstars of pop art. He has a point.
Pop was pioneered in 1950s London, where Hamilton, Eduardo Paolozzi and their avant-garde circle at the Institute of Contemporary Arts defined many of its central concerns. Their most memorable manifestation occurred in 1956 at the Whitechapel Art Gallery, in a dynamic exhibition called "This is Tomorrow". In an inspired section, Hamilton produced a show-stopping harbinger of pop art's fascination with comic-book heroes. By subtitling its show "This was tomorrow", the Tate now honours the prescience of that formative Whitechapel exhibition.
But by the time the 1960s arrived, British artists had moved on. Joe Tilson became haunted by images of the newly martyred Che Guevara. R B Kitaj echoed this sense of mournfulness by painting a harsh Denunciation, called The Murder of Rosa Luxemburg. The savagery of her death prompted Kitaj to turn his brush marks into weapons. His great friend David Hockney, emerging with fully fledged precocity from the Royal College of Art, painted a gaunt, emaciated male figure sitting mournfully on the front of a Typhoo tea packet.
Not everybody subscribed to this mood of foreboding. Phillip King's aptly named Tra-La-La could hardly be more insouciant, delighting in suggestive swellings and interwoven forms, improbably balanced on a gleaming pyramid. British sculpture in the 1960s was not afraid of swaggering showmanship, and David Annesley's undulating Swing Low is an outrageously ostentatious performance. But the most impressive exhibits offer a more disquieting vision.
Bridget Riley's Fall, an eye-wrenching black-and-white painting from 1963, has twisting rhythms reminiscent of Leon-ardo's overwhelming images where a deluge envelops the world. The following year, Hamilton produced Interior II, where a 1940s monochrome Hollywood starlet finds herself transplanted to a contemporary room. Like a character from an eerie film noir, she stares anxiously around her. Everything, from the archetypal swivel chair to the colour TV set, appears suspended in space. And we notice, with a shock, that the image on the screen shows the moment of President Kennedy's assassination. No wonder the starlet turns her blanched face away: she cannot bear to witness the death of the American dream. But Hamilton insists that we do, and that we meditate on the violence and fragility of a decade far removed from any wearisome "Swinging Sixties" cliches.
"Art and the 60s: this was tomorrow" is at Tate Britain, London SW1 (020 7887 8000) until 26 September