John Walsh: 'What's Obama doing in denim and trainers? Back to the skinny suits, please'

The Orange-winning novelist Linda Grant has been sounding off about her new book, The Thoughtful Dresser, in which she makes a heartfelt plea for the importance of clothing in our lives. Ms Grant, who likes to sport designer frocks and an abysmal (in the good sense) décolletage at parties, has no time for people who regard self-adornment as evidence of a trivial mind, and female designer-worship as proof of stupidity. She argues that clothes have a complex relation with our sense of identity; that they aren't just fine feathers that make superficially fine birds; that they tell us the kind of people we are and aspire to be. They assert our place in the world and soothe the assaults of fate.

Two details from her book stick in my head. One is that 11 September 2001 was the start of New York Fashion Week, and the Madison Avenue YSL store was expecting a consignment of silk peasant blouses, costing $2,500 each. Incredibly, on that morning of destruction, the store received 40 phone calls from women asking if the blouses were available. The other is the story of the women in Belsen concentration camp who were sent lipstick (nobody knows by whom) and seized it like a lifeline. "I believe nothing did more for these internees than the lipstick," wrote a liberating soldier. "At last someone had done something to make them individuals again; they were someone, no longer merely the number tattooed on the arm."

There's no male equivalent to the lipstick (I can't imagine camp inmates becoming excited by free aftershave) and history doesn't record whether the Ralph Lauren store on Fifth Avenue was inundated on September 11 with enquiries about a new range of gents' underpants. So does Ms Grant's argument apply only to ladies? Most men are herd dressers. They wear suits in studiedly neutral colours to fit in with each other; or they wear zip-fronted combat jackets and chinos to tell the world they're off-duty. Don't they get any more complicated than that?

Of course they do. Men can be quivering violets about clothes and what they say about them. Recently, I met a judge at a party (it's so weird when the High Court judges start looking younger) who told me how uncomfortable judges are with their new judicial garb. A year ago, the judiciary agreed to abolish horsehair wigs and black robes (except in criminal cases) and kit out judges in groovy blue gowns, designed by Betty Jackson. How, I asked, did the judges like their new look?

"They hate it," said my friend. "They think they lack all dignity and gravitas – especially if they're thinning a bit on top. They say they feel half-dressed without a wig." They're reduced, in other words, from stern embodiments of the super-ego to mere, humble, fallible-looking men.

Elsewhere, there are signs that chaps have gone a tad precious about chaps' clothing. The Daily Mail, always reliably dirigiste on garments, ticked off Alexander Lebedev and Andrew Marr for appearing in the latter's TV show in less than full canonicals. The paper called Lebedev "casually attired," but fairly smacked Marr around the head for wearing denims. "A disquieting sight," it shuddered. "No jeans, Andrew, please."

For some chaps, civilisation itself is threatened by the packaging of powerful men in working men's garb. In America, President Obama is under fire for his attempts to be casual in bright blue jeans and white trainers. "Get back into your sensible skinny suits pronto," is the message from the Democratic faithful: "Who do you think you are, George Bush?"

The semiotics of clothing is everywhere. Note how readily Sir Fred Goodwin got himself photographed by the media wearing his country-gentleman-at-a-shoot attire rather than anything that smacked of a) banking, or b) the City. Notice how Tony Blair, even in the boiling heat of Gaza, wears a tightly buttoned club tie to emphasise the unearthly gravity of his role as Middle East envoy; when he was PM, he'd have jettisoned the tie at the airport.

True, men don't go in for shopping as a leisure activity quite the way women do (Ms Grant is hilariously sexist about this,) nor do they, as a rule, possess the "must-have" gene that drives clever women to spend £1,300 on a Chanel bag. But we have our moments. Just don't ask us to give up our wigs before we're good and ready...