Tony Blair is not the only one to have a tenth anniversary. In 1997, a book I wrote on class was published. A Class Act argued that for the first two thirds of the 20th century, Britain had seen a steady improvement in social mobility. This had been made possible by grammar schools giving unprecedented educational opportunities to bright working (and middle) class children. For the final third of the century, however, the comprehensive revolution and decline in state-school standards reversed that social mobility.

My co-author was, like me, a journalist. With the new Government committed to education as its priority, we had high hopes that that reverse could itself be reversed. My co-author was soon in a position to do something about it, because he became Tony Blair’s main policy adviser and now, as Lord Adonis, is Schools Minister.

Yesterday, we learnt that more children than ever are being educated at independent schools – 40,000 more today than in May 1997. And this despite a drop in the number of children of school age. If they could afford to, even more parents would do the same. They believe – rightly – that standards are higher. Parents who strive for the best education for their children (often involving immense sacrifice to afford the fees) should be applauded. The problem arises only because of the reason they want to leave the state sector: the relative standards of state and independent schools.

We have an apartheid education system in which the barrier is not race but money. Fee-paying parents buy places in the best meritocratic schools, with the best meritocratic chance of securing a place in the best meritocratic universities, and thus the best meritocratic opportunity to get on in life. They compete on merit with their peers. But it is a stilted contest. Only the few lucky enough to have a decent education are able to enter it. The rest, however able they may be, are left behind.

The thread to the past ten years has been Mr Blair’s aim of giving all pupils the opportunity to enter that contest – to increase standards within the state sector so that all children have an equal chance of succeeding. But ten years on, and the apartheid barrier has grown even deeper. Those who can, pay. Those who can’t, stay.

It was understandable that Mr Blair’s first Education Secretary, David Blunkett, saw his task as cracking the whip. Confronted with the failure that Labour inherited in 1997, it would have been an unusual minister who did not want to impose himself from the centre. Understandable, but wrong. Under Mr Blunkett, there were so many directives – in 1998 alone he sent out 322, more than one for every day of term – that it was entirely self-defeating.

With Mr Blunkett’s departure in 2001, the emphasis shifted towards freeing schools from the monolithic “bog standard comprehensive” model and introducing a variety of school types, such as specialist schools and city academies. but sensible as this was, it still missed the fundamental point: parental power.

Why do parents choose to pay for independent schools? Because standards are higher. But why are they higher? The answer, of course, is precisely because parents pay. Independent schools have no choice but to respond to the needs of parents or suffer the consequences.

Take the experience of Clifton College. In the 1950s and 60s, independent schools were on the wane because state schools were doing a good job. When the comprehensive reorganisation hit in the mid1970s, Bristol’s top grammar school, which had higher academic standards than Clifton, chose to go private: Clifton found itself charging fees twice as high, while achieving far less impressive exam results. Its buildings were grander and its aura more impressive, but these counted for little. So Clifton had no choice but to adapt and turned itself into an attractive package offering exam results, facilities, sports and the aura of a top public school.

The introduction of league tables in the 1990s accelerated this process, showing up the chasm between state and independent schools but also forcing the more sluggish private schools to compete with each other. In 1996, the head of Cheltenham College was sacked because the school was not high enough in the table – a defining moment.

Introducing more variety into state schooling is a good thing. But it is not nearly enough. Schools that respond to the demands of parents succeed, whether in the state or private sector. It was government, not parents, that in 2004 made languages optional for pupils over 14. Languages are now compulsory in only 17 per cent of state schools and a huge decline in language teaching has followed. So parents have taken out their chequebooks and sent their children to schools where languages are properly taught.

Until state schools have a mechanism for giving parents the power of the purse string, it will be déjà vu all over again.

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