Even the most noble of queens can expect her loyal subjects to turn against her eventually. Be it a jubilee celebration too far or an over-zealous beheading, every serf has their tipping point.

While not a glorious ruler of any realm in particular, Madonna has had queenly status bestowed upon her for the majority of her career by a legion of gay followers. Having some kind of interest in what, or who, Madonna is doing seems to be a side-effect of being gay.

But now Her Madgesty has displeased her once-devoted flock. But what could it be? The slow degeneration of her music material? The ever-increasing cost of tickets to see her perform live? Her apparent disinterest in her career beyond turning up to the odd interview? Well, perhaps, but Madonna's crime seems to be the one that most of us commit eventually, if we're lucky - she got old.

Madonna has always delighted in challenging people's perceptions of appropriateness. From drying her stubbly armpits in a dirty washroom in Desperately Seeking Susan and flicking herself off on a giant bed while two gay men in conical bras looked on during the Blond Ambition tour to portraying the violence of war in the withdrawn video for American Life, no taboo seemed too small for La Ciccone to overturn.

Aside from a very staid decade or so where Madonna had a misguided, but spirited, go at being a submissive wife to director Guy Ritchie, her frankness, refusal to conform and power to shock have been her lifeblood; they have kept her career ticking over and front-and-centre for almost 30 years, a feat few other popstars - male or female - can boast.

Almost everyone has an opinion on Madonna, and the criticisms against her stack up like building blocks in a Guinness World Record attempt to reach the moon, but, thus far, Madonna has always been able to count on at least one demographic for continued, unwavering (and some might say blinkered) support - the gays.

Back when Madonna was still young enough to make it on to the higher reaches of those all-important, horrific 'Sexiest Women' lists that even the most highbrow of magazines insist on publishing, her stance as an awkward, complaining outsider spoke to the gay community in a way few have managed before. While her status as a pioneer may be exaggerated and seriously flawed, she at least gave the impression she was doing something new. She championed gay rights, spoke out in defence of her gay friends and hired gay dancers for her tours, and gay men and women lapped it up, long before 'Mother Monster' wobbled along in shoes shaped like an armadillo to tell everyone they were 'born this way'. Madonna's openness about sex, and ability to unashamedly enjoy having it, set a precedent for almost every female pop singer who came after her. And all was well with the world, because Madonna was still young and wrinkle-free.

Sex is no longer the sole property of the young. Everyone's eyes have been opened to the idea of silver shagging. Even Hollywood, the high altar of youth and beauty, has given the nod of approval. Diane Keaton and Jack Nicholson got down to it in Something's Gotta Give and Meryl Streep got a good seeing to thanks to Alec Baldwin in It's Complicated, but it seems Madonna's brand of sexuality is strictly off-message.

While it's no surprise that heterosexual men no longer have an interest in seeing Madonna in her knickers - they are, after all, force-fed a whole new bevy of beauties to adore, young enough to be their daughters and led by the shampoo ad juggernaut that is Cheryl Cole and pneumatic-lipped, thinking man's sex doll Angelina Jolie - it's much more disappointing to see that some of Madonna's detractors are the very men who gave her a leg-up to her pedestal in the first place. The gays have turned.

Trawl any so-called fan forum and you'll see the same disparaging remarks: outrage at her supposed 'pussy popping', refusal to 'grow old gracefully' (an awful, po-faced phrase whose retirement should come much sooner than Madonna's) and complaints that the erstwhile Material Girl is as old as their own mum. I know, right? She has birthdays! And the numbers keep going up and up!

"Ewww" said one forum member, in his late 20s, "nobody wants to see that dusty old vagina any more."

The irony being, of course, that gay men don't usually ever want to see a vagina, be it in the first flush of youth or swathed in mothballs.

"God, her scrawny arms are horrible," noted another armchair model scout, "and her hands are all gnarled."

Gay men, it seems, are now in charge of what is sexy and what is not. Despite their previous interest in women's looks usually being limited to slagging off their clothes (another totally ridiculous notion; why the hell do women listen to us?) and cooing over their hair once they've finished blow-drying it, all of a sudden these guys are the go-to experts when it comes to what the world should find shaggable, even if they don't want to do the nasty with it themselves. The idea that one's sexuality is redundant once grey hairs become the ruling majority leaves a much nastier taste in the mouth than any French kiss from Madonna would.

The media has long been puzzling over what to do about Madonna's refusal to put her dress back on. Since she deftly shimmied over that magic line into her 50s, actions previously deemed 'shocking' or 'thought-provoking' are now rebranded as 'sad', 'desperate' and 'attention-seeking', as if Madonna is in any way unique as a singer to want all eyes to be focused on her.

Vanity Fair scratched its chin over the whole topic of Madonna's sexiness as she prepared to turn 50 in August 2008: "Madonna made her fortune selling sex--what will she sell when the thought of sex with Madonna seems like a fetish?" it mused. Riddle-me-ree, indeed.

Of course, Madonna's recent 'nip slip' and arse-baring during live shows on her MDNA tour have fuelled the moans of those who wish Madonna would stop embarrassing herself, and them, and truss herself up in acrylic turtlenecks. Perhaps lacklustre sales of her last couple of fairly disappointing albums and criticism of her general disconnection from the material she produces have got her thinking more and that's why she's reaching around calculatedly to unhook her bra, but I doubt it.

If anything, Madonna's propensity for showing us what's inside her thong has led to lower returns when it comes to record sales. The much-hyped Erotica failed to ignite much reaction in the shops, except for "Ewww, she's got a toe in her mouth", and she was younger and tauter then. What hope for her now?

Whether the gays have tired of her 'pussy popping' (I have no idea what that actually means) or not, Madonna shows no sign of slowing down or capitulating. Images just released from the set of Madonna's latest single, Turn Up The Radio, show her spread-eagled in the back of a convertible, airing her bikini bits to an ever-disapproving world.

While my own interest in Madonna wanes with every so-so record or humourless personal appearance, the one thing I do think she's getting right is saying an emphatic "fuck you" to the ageist brigade, most of them still young enough to be able to think of their dotage as a far-off prospect, as fantastical as a fairy-tale ending.

But old age does not wait to be awoken by true love's kiss, nor validated by a handsome prince clambering up the ivory tower by way of a long plait of golden hair. Age is coming for all of you, and no amount of denial or mock horror at Madonna in her scants is going to change that. Madonna is living it now.

How many of her critics would be happy to walk so willingly, with head bowed, to the knackers' yard once they hit 50 and beyond? And when they reach that era - where young people would have you believe there's nothing but gummy smiles and osteoporosis, dicky bladders and forebodingly steep staircases - they should remember Madonna: uncompromising, unbroken, unrepentant.

Let's hope when the naysayers approach their twilight years they still have someone close at hand to tell them they look great in their underwear, that they're still hot and wanted. An empty bed, free of desire, can be just as cold and uninviting as a grave.

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