Mick Jagger turned 65 yesterday – thrust-out chest, strut, skinny jeans and all. In theory these defiantly virile rock dinosaurs, of whom Jagger is the grandaddy – the T Rex, if you will – ought to be horribly embarrassing in a “Put it away, gramps” kind of way. In practice they are rather marvellous, not least because chances are that if your dad in his sixties or seventies doesn’t necessarily do the pipe and slippers thing, he has Mick and the slew of lesser dinosaurs to thank.

I don’t know whether I say this because I am now middle-aged myself (I went to see the Stones at Wembley in 1982 and remember thinking they were quite sexy, for gnarled old people), but it certainly seems to be the case that leathery old rockers who would have been greeted with howls of derision 20 years ago are now an accepted part of the landscape, still thrusting away and putting it about and generally adding to the nation’s gaiety.

They have also, unpredictably, become role models for older people – and are admired by young people in a way that used to be inconceivable. When I was young, we no more bought music made by people old enough to be our grandpas than we wore Crimplene slacks. The Crimplene is still out in the cold, but rock bands whose collective age is 400 or so are now beloved of many teenagers.

It must be intensely cheering for their baby-boomer contemporaries, for whom Jagger, Keith Richards et al were raver role models and much-revered lords of misrule, to see that being pensionable (which is an anagram of “a noble penis”, appropriately given Jagger’s knighthood) is no bar to bad behaviour or success, both personal and popular.

There is an increasingly noticeable divide in the way pensioners live: on the one hand you have Jagger, with his consorts and children and priapic lights undimmed, and on the other you have people such as my friend’s mother who, although fit as a fiddle, checked herself into a sheltered housing complex at the age of 62 and is fond of uttering the immortal line “My cuddling days are over”.

Jagger’s cuddling days are very much still with us, as are those of his bandmate Ronnie Wood, 61, who recently did a bunk with a 20-year-old waitress for a drinking binge (Wood is an alcoholic), before checking himself into rehab and back into the arms of Jo, his long-suffering wife.

Granted, Jagger and Wood are rock stars and my friend’s mother is not, but observing the whole issue of old age tends to persuade one that those who have lived life to the full seem to have a rather better time of it than those who have led an unremarkable, proper, 2.2 sort of existence.

It is also clear that Jagger’s baby-boomer generation has completely reinvented old age: before them, the idea of anyone having what newspapers sometimes euphemistically call “a full and active life” – meaning a sex life – was troubling at best and repulsive at worst. Tell that to the 20-year-old who fancies Helen Mirren.

A great deal of this divide depends on social class: people who have been blue-collar workers all their lives, and are physically knackered, age more rapidly than their contemporaries who spent the summers lounging about in Marrakesh: they didn’t spend the 1960s partying and being out of it and, unfairly, it seems both to have aged them prematurely and to have reinforced their already rigid notions of what old age is and how you deal with it (by wearing cardigans and waiting for death).

It will be interesting to see how the generations below mine, for whom cheap drugs and cheap travel – and therefore the opportunity to live like a rock star, or the tabloid version of one – became widely available regardless of class or income, will approach their own old age: I expect fighting for the right to party well into your eighties will become the norm rather than the exception, and that the rock dinosaurs we once derided for being unseemly and faintly absurd will turn out to have been pioneers, as instrumental in redefining old age as better healthcare, more vitamins and the wonders of Botox.

What can the longevity of Jagger and his ilk be attributed to? There is the question of physical robustness, obviously, as evidenced by the creaky but still functioning Richards, a man whose excesses were so extreme that to catalogue them would take up two pages of this newspaper. But I think emotional robustness is really the key: today’s 65-year-olds, be they rock stars or ordinary people, were brought up to look after themselves and to be self-reliant. They just got on with it.

There is a clue in a recent interview the Stones gave to The Times, in which Jagger, apropos of the tribulations of Amy Wine-house and Pete Doherty, says: “People go through all this stuff but now, compared to when we were going through all our similar sorts of times, people didn’t really know so much about drugs or they didn’t have rehab centres. Well, they did but I’d never heard of one.” Wood: “You were considered mad if you went to one.” Jagger: “There weren’t the sort of support systems that people can have now, so you had to be your own support system.”

Compare and contrast with the current approach, where every two-bit wannabe desperately seeks out victimhood and is nothing without the obligatory stint in rehab, often for imaginary reasons, such as a lone two-day bender or waking up feeling a bit gloomy one morning (this is called “having bipolar” and is terribly popular, as in “My bipolar’s playing up again”).

Rehab, or what passes for it these days (as with everything else, good treatment centres are few and far between), lasts about a week, after which you’re magically cured. So there are two components to ageing disgracefully and making it work à la Jagger: dissipation, but only provided you have no self-pity about the inevitable troubles – be they drug, alcohol or wife-related – you will find yourself beset by.

Troubles and anxieties are the enemy of youth; what Jagger and his friends demonstrate is that you can do whatever you want to do if you just pick yourself up and carry on afterwards, without collapsing into a very 21st-century heap of emotional incontinence. It’s a dying art and one that those of us headed towards our pensions might do well to aim for.

+ I can’t understand why the actress Sienna Miller is getting one of her habitual media batterings for having been photographed kissing Balthazar Getty, the 33-year-old heir to the Getty oil fortune. Getty has recently separated from his wife Rosetta, with whom he has four young children; whether the separation occurred pre or postSienna is not clear. Miller is derided in the media and all over the internet for being a “home-wrecker” and a “husband-stealing bitch”; one especially poisonous celebrity blogger has renamed her Sluttyiena (rather a laboured pun, that).

Why? Did she dump her husband and four children? Did she run away from all her responsibilities for the sake of a quick snog? No: she has no responsibilities. She is a single 26-year-old with no attachments and no kids. She is surely free to do whatever she likes, without being answerable to the self-appointed moral police.

One single woman, one married father of four – and who gets it in the neck? The woman of course: the witch, the enchantress, whose siren call drives poor blameless men to distraction and causes them to behave reprehensibly through no fault of their own, abandoning their children and dumping their wives.

It’s pathetic. Miller kissed a man who presumably told her he was single – or as good as. If someone behaved badly, it sure as hell wasn’t her.

*****

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