Peter York: The secret and changing life of the private members' club

Clubs exist to celebrate groups on the up and to console groups on the down – to confirm what Tom Wolfe described as the here-we-all-are moments of the status-sphere, the point at which a group and its members feel most glowing, most mutually reinforcing. And clubbability is forever being reinvented for every kind of Great World and half-world as it pitches up with money to spend and a reference group lodged in its subconscious.

A brouhaha at Soho House last week over the dress code, and the pitching for membership of the Garrick Club of national treasure Joanna Lumley, have pushed blinking into the limelight this traditionally dusky, twilight world of mahogany doors and signing-in books. Few passers-by even recognise the austere façade on Pall Mall or the discreet side-street door behind which exists a subset of society, leaning on old contacts or forging new connections. But private members' clubs have been a great growth area for the past 20 years.

London clubland divides itself between the St James's refuge for toffs, and the Conquest of Cool, for the arts and media. The Garrick falls between the two, being decidedly traditional in the leather-chair sense, but rashly teetering on the edge of Covent Garden and attractive to the Paxman-Fry tendency. The majestically conservative Reform Club, too, likes to cling paradoxically to the tradition of dissent from which it takes its name.

But who drives to the RAC Club, and what exactly is Soho House for? Is it your reference group? Do you see your heroes going there? Do you latch on to the Soho House group aesthetic, or is a 19th-century palazzo by Sir Charles Barry or Robert Smirke nearer the mark for you? My marginal acquaintance with the Chipping Norton set included an Oxfordshire party whose invitation had the multiple hosts – Rebekah and Charlie, etc – appearing in first-name pairings on the invitation. We know who we are. In a few years, half London will claim to have been there. Chipping Norton was an informal club in the making if ever there was one.

Soho House is certainly fascinating; a microcosm of the modern world with its new hybrid mix of the arts, media and marketing members. It is different from the Eighties hub, the Groucho Club, because it's somehow more replicable elsewhere, especially America, and, despite its name, only loosely tethered to London W1.

Soho House is a nice place to have a meeting, to work up a project. Pleasant rooms, reliable food and a sort of implicit dress code – knowing casual, rather than the smart casual people bang on about. Tod's, dark linen, soft shirts with teeny open collars and all that expensively sub-fusc kit.

And then, rather startlingly, the implicit became explicit. Peter Bingle, 51, the chairman of Bell Pottinger Public Affairs, part of Lord Bell's Chime empire, was banned from Soho House for wearing a suit and tie. Bingle certainly thinks this was his sin – and the letter from Soho House "explaining our casual dress code which you are clearly disregarding" seems to confirm it.

What else might he have done wrong? What else could have led them to "ask you to refrain from entering any of our clubs for a period of six months"? Being a lobbyist? Being a Tory? Being 51? Or is it that he has that plump, smiley Worker Daddy of bourgeois Twickenham look to him? He acknowledges this side of things – he told the London Evening Standard that "maybe my suits aren't very good". "But would they ban Gilbert and George?" he asked me. (Of course I've never seen G&G open-necked; it's unimaginable.)

But it couldn't be clearer: "Our casual dress code...". The new synthesis of Soho Bohemia, Nineties Hollywood "player" culture and British marcoms demands a casual uniform. Anything else would obviously upset other members' quiet enjoyment, remind them of Twickenham and Gerrards Cross, of black tie rubber-chicken dinners in hotel ballrooms, of raising your glasses to the Queen. Of an Armstrong-Siddeley, Austin Cambridge world that might reach out from beyond the grave and pull them back into Middle Britain. The Groucho Club's manager – representing louche Eighties to Soho House's more careerist Nineties ethic – said in the same Standard piece that they "have no dress code whatsoever".

If you arrive at a Pall Mall club without a tie they'll give you one (usually hideous, as a punishment). But they won't bar the door to you for not looking the part otherwise – any sort of dark suit affair, any sort of mail-order formal shoe set-up will give you the run of St James's.

What, you wonder, did former assistant commissioner Andy Hayman wear to Soho House when Neil Wallis, then a NOTW deputy editor, so famously took him to lunch there? Did Wallis brief Hayman on the "casual" dress code? Who did or didn't wear a tie? You long to know.

No one wastes a minute on the dress code in the Garrick's 1864 big, handsome Italianate home (by Frederick Marrable). It's as clear as in Pall Mall, though the members tend to be that bit more colourful in the tie and waistcoat area. But the lovely actor Hugh Bonneville, in putting up for membership the irresistible Lumley, has alighted upon a newcomer perfect in every particular except that the Garrick – the richest, longest waiting-listed gents' club – doesn't admit women. They go as guests – sometimes even to sit at the big centre table – but not as members. Now every Garrick man and boy will imagine Joanna across the table from him on a constant basis.

London clubland – the old kind and the new – will survive these modest strains. Soho House is big in its world, but if you can't live with the alternative dress code, there are other places. And the Garrick will probably invent a charming fudge, with Joanna rebadged as a Gurkha general or a foreign head of state.

The economy's a more serious worry; as each new group, from 19th-century plutocrats to Nineties hedge-funders, feels rich and arrived, so new club ideas get backers, get built and launched, and the better old ones get a transfusion of new members. But with the euro imploding and the US on the brink, that expanding universe of clubland looks distinctly shaky. London's so global, so multi, it's difficult to see exactly how it'll play out. Will every other rich person in the West huddle here for comfort? Non-doms already own 60 per cent of London's prime and super-prime property. And it's the number one destination for Flight Capital.

Can the notion of the club exist beyond these shores? The diner in Palo Alto, California, when I first saw it in the early Nineties, already had the look of somewhere rushing feet first into legend. A real Fifties diner – that most demotic, democratic invention of America in its Golden Century – not a pastiche, it was already smart and consciously preserved. I'd been speaking in a debate at the extraordinary Hispanically-styled and extremely rich local Stanford University and, like any Brit then, wanted to see the town that took over the world.

I started imagining that in a time to come there would be the Bill Gates Memorial Vitrine, the Steve Jobs T-shirt mounted and framed, the brass-plaqued table where the first Silicon Valley private equity guy – open-necked shirt of course – did the first big deal. The prices would quadruple and it would become a private members' club. And one day, Hugh Bonneville would propose Joanna Lumley for membership.