Today, as you may have heard, is apparently the 50th anniversary of the Rolling Stones’ first gig.

Ten years ago, I wrote a piece – with some assistance from Andrew Loog Oldham – on the occasion of their 40th birthday, which it seemed salient to dig out today. A lot of this still holds true, I think, though in the intervening years the pantomime has seen Mick Jagger’s capricious and unsentimental approach to his own history become even more pronounced, as well as an event that seemed pretty implausible back in 2002; one more good Stones album, “A Bigger Bang”, that deserves a lot more love than it generally receives. Happy birthday, anyhow….

How, one wonders, will The Rolling Stones celebrate their 40th birthday? A group hug and shared tears are hardly the style of these most unsentimental of men. An argument, perhaps, is more their style. One about the whole idea of their birthday, for instance. As a flood of compilations, reissues, memoirs, live shows and gilded souvenir cash-ins commemorate their anniversary, Jagger has questioned the veracity of the whole business. Officially sanctioned history points to July 12, 1962, as the start of their extraordinary career – a gig at London’s Marquee Club. But with an unusually conscientious flourish, Jagger disputes the date, suggesting sometime in 1963 – when drummer Charlie Watts arrived to complete the first classic lineup – as more apt. A dispute about the very fundaments of their existence seems fitting.

Or how about a juicy personality clash between Jagger and Keith Richards? The animosity between these two songwriting partners has only added to the legend of the Stones over the years. Often, it hinges on their battling aesthetics: Jagger the social climber, the moderniser, the shameless celebrity butterfly; Richards the recalcitrant old buffer, stubbornly loyal to rock’n’roll tradition, disdainful of his foil’s pretensions. Another entertaining feud kicked off recently, when a magazine asked Richards his opinion of Jagger’s knighthood.

“What did I feel when I heard about the knighthood?” he said. “Cold, cold rage at his blind stupidity. It was enraging, I threatened to pull out of the tour – went berserk, bananas! But, quite honestly, Mick’s fucked up so many times what’s another fuck-up?”

Not a subject, then, for the old devils to discuss over post-gig canapes. But what is, realistically? What can these men have left to say to each other after 40 years together? No-one works with the same people for that long in the real world, let alone in the emotionally heightened, perpetually adolescent sphere of rock’n’roll.

There are many remarkable things about The Rolling Stones, but it’s an inevitable fact that, in 2002, the one that’s most striking is their absurd longevity. In July 1962 The Beatles were yet to release a record, Bob Dylan was three years from discovering electricity, Liam Gallagher was ten years off being born, and rock’n’roll was meant to be merely a passing fad.

That it has been sustained for so long – become embedded in our culture, even – is due, in an enormous amount, to The Rolling Stones. It’s not just the excellence of their music, or their business genius. No, The Rolling Stones set a template for rock’n’roll that was much bigger than music. Rock’n’roll was inexorably hooked up with sex and drugs. It articulated adolescent rage, rebellion, boredom and pettiness better than any other art form. It at least pretended to be dirty, provocative, confusing, not a little menacing.

And it found its purest embodiment in their skinny, uptight white bodies. The Beatles might have been charming, easier to assimilate and, fractionally, musically superior. But the Stones were far more successful at capitalising on the principle of a counterculture. They were A Threat. Five young men who were taken to court for urinating in the street, who were regarded with fear and despair by right-thinking parents and who, with the canny assistance of their manager until 1967, Andrew Loog Oldham, made nastiness marketable. What could be easier to pull off and yet so radical, so appealing and so lucrative?

“I always imagined The Rolling Stones lasting, one was just not aware of in which form,” says Oldham from his home in Bogota, Colombia. “They were very professional and dedicated from the first moment. I told them who they were and they became it. They wore the bad boy tag like a suit of armour, and drew a veil over how professional they really were.”

But, as Oldham writes in the second volume of his compelling autobiography, 2Stoned: “Violence and anger would become permanent fixtures.” Elements which were not, of course, always controllable. Drug busts, the death of guitarist Brian Jones (found floating in his pool in 1969), the violent murder of a black fan by Hell’s Angels acting as security during the 1969 show at Altamont – these were hardly desirable career details. But truly great bands tend to have a mythological momentum wherein contrivance and accident become intertwined. And so tragedy and brutality only stoked the legend of The Rolling Stones.

By then, too, they were too big a business to be stopped. Had become so big, in fact, that it’s hard to imagine the international market ever allowing them to stop. The sales of new product might have dribbled away in the early 1980s, but the justifiably-named World’s Greatest Rock’n’Roll Band have continued to be omnipresent ever since: refracted through the surliness and conspicuous consumption of every band who has ever decided to be self-consciously rock’n’roll; through the regular globe-straddling tours; and, naturally, through that glorious and milkable back catalogue.

The Rolling Stones’s 40th anniversary is being marked by a substantial revamping of that auspicious archive. First up is Forty Licks, which endeavours, with some success, to boil down their gargantuan oeuvre onto a couple of hit-stuffed, consistently thrilling CDs. It’s followed in October by 22 albums from the 1960s that have been diligently restored and remastered. Cutting through the record-collector hype that surrounds the whole project, there remains something elemental about much of this music which still makes it gripping. It’s the sound of tension and power, of five Englishmen moving through homages to American bluesmen and coming to terms with the huge possibilities opening up to them. The riffs – Gimme Shelter, Satisfaction, Start Me Up – are unforgettable. Jagger, meanwhile, is busy creating his own grand romance: a mixture of superhuman virility and teasing camp. “I was born in a crossfire hurricane,” he claims in Jumpin’ Jack Flash – unlikely for a son of Dartford, Kent. “But what can a poor boy do except to sing for a rock and roll band?” he mugs heroically in Street Fighting Man, ever the expedient revolutionary. Critically, the Stones proved that the blues and its derivatives were not dependent on sincerity. Few singers have ever sounded so charged and engaging, and yet so obviously removed from the hurt they describe.

“They started out as The Rollin’ Stones,” explains Andrew Loog Oldham, “six blues-struck musos glued to a music born of slavery, share-cropping and blacks. They grabbed hold of it with their educated little white middle class fingers and honed it into their own. Mick and Keith learnt to write and the Stones notched up a batch of mid-1960s singles that define the time. I became redundant to them, Brian died and they moved into the excess and self-adulation that the Seventies begot and made more music that defined the time.

“More importantly, they mastered one side of the proceedings that I deal with in 2Stoned, and that is that today’s artists don’t need a Svengali, they have to be one. Look at Eminem, Madonna, Cher, Tom Cruise, Mel Gibson … any of the current artists who can take a town or open a film. They know exactly who they are and how to do it – as do The Rolling Stones.”

It’s strange how a desire to do whatever you want can pan out. As stroppy post-adolescents, The Rolling Stones epitomised a certain petulant negation of establishment values. Put simply, they wanted their own way. With age, that same insistence on complete control became codified as a bullet-proof business plan. As Oldham says: “The Rolling Stones are definitely part of the establishment, or in more specific terms, providers of the establishment … They use the system. CDs are just another item in the list of goods they have for sale, so don’t talk to me about their new single. It’s just a surface, seductive invitation to a catalogue extended by the masters of the game.”

This is how these ruthless players can appear to be against the system while simultaneously running it – by making disaffection a copyrighted commodity. In the hands of middle-aged gentlemen, it sometimes seems a little ludicrous, but then, so much does about the Stones. Take Jagger’s irregular grapplings with fashion, for instance, that usually result in a hiply produced, commercially catastrophic solo album like last year’s Goddess In The Doorway. Or his comically inexhaustible libido, and the carelessness with which he greets another tabloid expos of his love life.

“When Mick Jagger had his solo recording out,” recalls Oldham, “I stated that the ambition that had been attractive in the 1960s could turn – in the light of his and Paul McCartney’s solo efforts – when one is over 50 into an embarrassing disease. Tough, but light compared to what Keith Richards had to say. It goes hand in hand with the art. But a musician is entitled to play or sing, it’s their lifeblood and reason to be living. He or she can only spend so many days of the year being comfortable at home.”

Or take rock’s most miraculous survivor, Keith Richards, and his increasingly deranged take on outlaw style: the bits of feather in his hair that make him look, presumably intentionally, like a Home Counties Sitting Bull. Or his clownish, geezerly sidekick Ron Wood, the enthusiastic new boy who’s only been in the band for 30 years. These are not, by most standards, men growing old gracefully.

But perhaps this is one of the most radical innovations of The Rolling Stones. They force us to look at ageing in a new light: they aren’t merely dallying with the affectations of youth, they’re staying loyal to the tenets of a youth culture – a look-at-me decadence, a rebel theatre, an idiosyncratic style – that they helped to invent.

Look at them in a new picture in the booklet that comes with Forty Licks, where the four current members are wedged onto a sofa. Richards, on the left, is pretending to be asleep, his head resting on Wood’s shoulder. Loyally, Wood has one eye open and is equally slouched. Drummer Charlie Watts looks as urbane and detached as ever, a thin smile of private amusement on his lips. And Jagger, on the right, is hilarious: sat bolt upright, staring with prurient disgust at Richards. Here, their differences are cultivated, and internal conflict becomes yet another marketing tool. Here’s the last gang in town, one that has stuck together through thick and thin, but only after protracted negotiations between each other’s people.

So, are The Rolling Stones merely the picture in rock’n’roll’s attic, wrinkling up while the genre they helped create sustains its youthfulness? It does seem wrong to call them the music’s consciences, or guardians: after all, they’d never take on a job with such hazy financial rewards.

But at this point, it looks very much like they’ll go on forever. Wise businessmen don’t abandon one of the strongest brand names on the planet, after all. As the 40th anniversary tour trolls round the States and begins its tentative movements across the rest of the planet, plenty of people will call The Rolling Stones a travesty of their former selves. But really, they’re perpetuating their legend, not debasing it. For if one of their principles is that rock’n’roll is innate, a calling, then it’s necessary for them to be seen to pursue it until the absolute end. They’re the proof that this music refuses to fade away, in spite of how transient it has appeared at times over the past 40 years.

And finally, they’re a band that demand analysis but simultaneously transcend it: there’s only so much you can intellectualise about something so immediate and, still, exhilarating.

“We have so much time to fret and gossip when The Rolling Stones are off the road,” concludes Andrew Loog Oldham. “But once they are back on it, it’s theirs and that’s all there is to say. And this time they’ve really grabbed the tit and heart of America. They are a forgiven Enron: pure materialanza; able, because of the force and the memory, to entertain a post-9/11 America that Bruce Springsteen, because of the home-grown luggage, can only console.”

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