Only one group of people in our society is never expected to need role models, and that group comprises middle-class white men. Women, on the other hand, are expected to need role models for everything, from drinking to working to getting pregnant to wearing a stud in their lip. Black people are also said to need them, primarily for professional ambition. Even working-class boys are expected to want role models, although for some reason only footballers are ever held up as possible templates for them.

Only one group of people in our society is never expected to need role models, and that group comprises middle-class white men. Women, on the other hand, are expected to need role models for everything, from drinking to working to getting pregnant to wearing a stud in their lip. Black people are also said to need them, primarily for professional ambition. Even working-class boys are expected to want role models, although for some reason only footballers are ever held up as possible templates for them.

But middle-class men can go it entirely alone, and that's a measure of their power. When Julian Fellowes wins an Oscar, who comments that middle-class Englishmen now have a great new role model? When Stephen Byers ducks and dives and weaves his way towards disaster, who wails that he is letting down all the young men behind him? That's because middle-class men are assumed to be grown ups, who can make their own choices about what they are going to do in their lives, without constant inspiration and uplifting and feel-good pep talks.

Women and black people, however, have role models, they celebrate role models – and when they reach a certain stage in their success, they become role models.

I'm not saying that the contemporary cult of role modelling is entirely off the mark. If any group is being held back primarily by social attitudes, then a single role model who has flown in the face of prejudice can set a grand example – to inspire her fellows, yes, and also to explode the attitudes of her enemies. That was the force of Margaret Thatcher as a role model for women. On this, the week of her final retirement from public life, some women journalists have taken the opportunity to explain again why she was such a bad influence on feminism. Sure, she wasn't in the slightest bit interested in equality for others. But the very fact that she existed at the apex of British power made her a concrete rebuke to all those who doubted that women were capable of moulding a nation's political life.

The force of the single role model who goes where no other person from that social group has yet gone can still be staggering. Weren't you surprised by quite how powerful the moment at the Academy Awards was when Halle Berry reminded us that a gate had just swung open? She stood on the Oscar podium and lived out, in front of millions of viewers, her transformation from talented actress to role model.

Mock it if you will, but that's what her speech laid out. She paid tribute to those women – "Dorothy Dandridge, Lena Horne" – who had gone before her and been her own inspiration; and the women whom she hoped would come after her, "every nameless, faceless woman of colour that now has a chance". And she threw in Oprah Winfrey as well, just for the hell of it, "for being the best role model any girl can have".

This idealism transformed the sugary dullness of the Oscar ceremony into something spirited and hopeful. The desire to crash through every socially imposed boundary, and to gain inspiration from how others have tried to do the same, has been a vital strand of the movements for female and black equality. In the early history of feminism, it was a constant motif. If you turn the pages of the history of women's liberation, you find one or two individual women taking a brave new step – speaking at a public meeting, say, or smoking in public or sitting a university examination – and a few pages further on you find that thousands of women have followed her and that such behaviour is simply taken for granted.

That's the most powerful aspect of the idea of the role model, that when one person opens a gate, others can pile through it. But recently, the theme of the role model has become weirdly debased and overused. Every woman in the public eye is moulded by the media to provide an "example", an "icon" or a "heroine" for young women – or castigated if she doesn't. One of the most absurd pieces of journalism I have read recently put Victoria Beckham and Arundhati Roy as the top female role models of our times. Apart from their gamine hairstyles, I'm really not sure what the glossy devotee of Louis Vuitton and the politically active novelist have in common. This label of role model is being used to suggest that any woman in the public eye must be empowering for others, simply by virtue of the fact that she is female and famous.

It's not just women who are suffering from being boxed into role-model status once they get to a certain level of fame – although women have the worst of it. Footballers, those supposed role models for working class boys, were recently informed, via a court of appeal judgment on an anonymous footballer's struggle with a newspaper that wanted to publish shaming details of his private life, that because they are role models, footballers now have no right to privacy.

Indeed, women in the public eye seem to have accepted that they will be constantly picked over for the messages they are sending out to young women – does Kate Moss party too hard to be the standard for young mothers? Was Victoria Beckham's lip stud a good example to set the young? Was Britney Spears too rude to her fans to be a good role model?

Role models – or heroines, which is a less gooey term – can be a great inspiration in knocking down old expectations and suggesting new ambitions. But isn't it just a tad patronising to assume that young women are in constant need of icons to model every detail of their lives upon? And when those role models have become as lightweight as they are at the moment, then isn't it bizarre to think that women would want to draw inspiration from such people, rather than from the brave and interesting and rebellious women they see around them in everyday life? As Christopher Hitchens said recently in this newspaper: "Role model is on my list of banned expressions. It's partly new-age gunk and partly celebrity culture. I never use the term."

So should we throw out the role model for good? It seems to me that the one group never asked by popular culture to contemplate its role models might be the one group that could benefit from new icons. How about some role models for young middle-class men that would provide them with pointers for change in a changing world? They would have to be people who could buck the trend, just as female role models once bucked the trends, role models who could provide images of caring, of community, of co-operation, of parenting, rather than of individual success and ambition – and those must be the hardest role models to find.

But as for everyone else, perhaps it is time to decide that a heroine does not always have to be a role model. Of course, we all have our personal heroes and heroines, and we can all cheer when women and black people get to the top, but maybe we can allow them to be mavericks and individuals rather than cheerleaders and role models. For one thing, that might allow us to realise that we don't need templates to show us how to live our lives. And for another, it might help us to see that if we really want equality, that takes more than a role model – that takes a revolution.

n.walter@btinternet.com