ETON REMAINS one of the most emotive four-letter words in the English language. A few years ago, the notion that an Old Etonian might be in a position to become Prime Minister would have been dismissed as fanciful. According to conventional wisdom, David Cameron’s old school tie should have strangled his chances from the outset.

Yet Cameron won the Conservative leadership in spite of, and not because of, his privileged education. His new job is a sign, not that Old Etonianism matters, but that it does not. Most grassroots Conservatives, it seems, simply did not set much stock by where he went to school. That is surely proof that the old class divisions are slowly becoming irrelevant.

An education at Eton costs £23,000 a year, during which pupils (known as “scholars” or “Oppidans”) learn to play a wall game that no one else understands or cares about, and submit to what the Old Etonian author Nick Fraser calls “a bizarre, quasi-Hassidic dress code”. Only in a genuinely classless modern society could you do this to a young man and not inflict lasting damage to his electoral prospects.

For some, the E-word is still the mark of Cain. “He’s an Old Etonian,” jeered Gordon Brown, to a chorus of sniggers, at the Labour Party conference. The Chancellor is partial to the class-based attack, and he plainly intends to use Cameron’s background as a cudgel against him. For people such as Brown, the very word Eton still sums up stiff collars, stiffer manners, noses of toffee and spoons of silver.

The press attaches the Eton label to Cameron at every opportunity, but whether a purely negative association still holds true for the population at large is more uncertain. To the extent that Cameron has yet impinged on middle-class consciousness, he is seen as a polite young chap with a pregnant wife who has an appealing ankle tattoo. Where he went to school seems a matter of relative indifference: Oppidan, Schmoppidan.

Alan Bennett described Old Etonians as “exotic creatures” but Cameron, so far from encountering inverted snobbery when he visited the East End this week, was commended by local leaders for overcoming the disadvantages of his class and education: “His Eton background doesn’t stop him getting involved,” one remarked.

We have come a long way from the days when an Eton education was a passport to political power. There have been no less than 19 prime ministers educated at the school, including Walpole, Pitt the Elder, Gladstone, Eden, Macmillan and Douglas-Home, whose Cabinet contained 11 Old Etonians. Alan Clark (himself an Old Etonian) referred to “government by means of an Old Etonian cabal”. This was not intended as a criticism.

That all changed with postwar egalitarianism. Margaret Thatcher had no special affection for the breed, and fired four Etonians from her Cabinet in 1983, prompting Macmillan (who had nine fellow Etonians in his 1956 Cabinet) to remark, with an anti-Semitic edge, that there were “more Old Estonians than Old Etonians” running the country.

Once an asset, an education at Eton became a serious political liability. When Douglas Hurd was challenged over his Eton education during his Tory leadership bid, he was left sputtering: “I though I was running for leadership of the Tory party, not some demented Marxist sect.”

(Old Etonian) George Orwell picked up Wellington’s apocryphal remark that Waterloo “was fought and won on the playing fields of Eton”, and turned it on its head, pointing out that “the opening battles of all subsequent wars have been lost there. One of the dominant facts in English life during the past three quarters of a century has been the decay of ability in the ruling class.”

Cameron may be able to turn his Eton past to his advantage by publicly playing it down at every opportunity. “It isn’t the back story that matters,” he insists. “It’s not where you come from, but where you are going.” The irrelevance of social origins is an argument more traditionally heard from the Left than the Right, and if Tony Blair can overcome the disadvantages of an expensive education, then so can Cameron. The difference is that Eton, unlike Fettes, has an image, for good and ill, that is deeply embedded in British national culture. One hint of arrogance or entitlement on Cameron’s part and his schooldays will return to haunt him.

My own experience of Etonians (and some of my best friends . . . etc) is that they are invariably good company and often extremely hard to read. Many, acutely aware of the baggage they carry, instinctively rely on self-confident self-effacement, allied to easy charm and a carapace of good manners that can be quite impenetrable. Most studiously avoid the subject of school.

Cameron is no exception, yet his election provides a remarkable reflection of the way British society and class structure have evolved. Eton, once a badge of prerogative, has been relegated to a mere “back story”. The inverted snob who sneers at a public school education seems as archaic today as the toff who looks down on his state-educated peers; the boot-straps bore who bangs on about having come up the hard way is as tiresome as the upper-class twit who assumes privilege as a birthright.

For centuries, Eton induced a weird, knee-bending deference; for the past 40 years it has tended to provoke knee-jerk antagonism. It is a reflection of a mature society that the connection should now elicit, from most people, little more than vague curiosity or polite indifference. Where the Tory leader went to school ranks alongside the fact that his wife’s father’s great-great-grandmother was the daughter of the 8th Duke of St Albans, who was descended from Nell Gwyn: intriguing, but hardly of vital importance. What matters is not where he comes from, or whether he played some arcane school sport involving an old wall, but how he performs in the much bigger game he is now playing.

One measure of that will be whether, six months from now, the man who would be “Dave” is still routinely referred to “Old Etonian David Cameron”.

Times Recommends

• Britain doesn’t need a dose of shock therapy
• Why the sea eagle has no right to land here
• Let older women have a voice at the BBC