In 1944, R A Butler was asked what he thought the long-term effects of his great Education Bill would be. “Well,” he replied, “it will be as much social as educational. I think it will have the result of welding us all into One Nation . . . instead of the Two Nations which Disraeli talked about. Then I hope it will lead to greater happiness and efficiency for those in industry when they grow up.”

Though the Butler Act made comprehensives possible, what actually developed was the selective tripartite system which led to the opposite of Butler’s ideals. Socially divisive and educationally wasteful, it institutionalised failure in a system that concentrated on the brightest few and contained the rest. Although it failed, selection is now back on the agenda.

Though the Labour party has recently scored an own goal with the Harriet Harman row, the comprehensive ideal is neither socialist in origin nor the preserve of the Labour party. Influenced by the philosopher John Dewey, the system was first developed in the virulently anti-socialist United States which was almost entirely comprehensive by the 1920s.

In Britain, the post-war Labour government rejected this route, so local education authorities such as Conservative Surrey were prevented from going comprehensive on the grounds that the 11-plus made grammar schools egalitarian. The first council to go comprehensive was Conservative Leicestershire in 1957. In comparison. the Labour-controlled Leicester City remained rigidly selective.

The tripartite system of secondary grammar, technical and modern schools, heavily influenced by the fraudulent research of educational psychologist Sir Cyril Burt and the defective thinking of the 1943 Norwood report, simply did not work.

In most of the country the secondary technical schools never materialised. The parity of esteem between grammar and modern schools that Norwood had envisaged never happened, nor did the second chance that children were supposed to get at 13.

As the Gurney-Dixon reportof 1954 showed, only 13 per cent of those who failed the 11-plus later transferred to grammar schools, and a very high proportion of those left school at 15 without qualifications.

Most children went to secondary moderns and also left at 15 with few if any qualifications. This was hardly surprising, for if you tell 11-year-olds that they are failures you get a self-fulfilling prophecy. As the 1967 Plowden report put it, “boys and girls tend to live up to, or down to, their reputations”.

Things were different at private schools, where many parents put their children in for the 11-plus in case they later transferred to the state system. The private sector ignored the exam. Those who failed were expected to get their O-levels and A-levels and go to university just like the rest, so most of them did.

Parental pressure led to the abandonment of selection almost everywhere, thanks largely to Margaret Thatcher. When Education Secretary between 1970 and 1974, she approved 91 per cent of the 3,600 secondary reorganisation plans put before her and closed more grammar schools than any minister before or since.

It is fashionable now to knock the education system and to claim that our schools are failing. Some are, and many could achieve more, but most have managed to raise standards significantly despite the difficulties of coping with a great deal of change.

Children leave school today with a far higher level of attainment than they did during the days of selection. The far larger numbers gaining GCSEs, A-levels and going on to further and higher education are evidence of this. The comprehensive reforms have been a central part of this process.

It is all a question of what is expected of young people. Under the old system the majority who failed the 11-plus had low aspirations. The move to comprehensive education means that we now expect the majority to do a great deal better. Reforms like GCSE and general national vocational qualifications are geared to stretching people with a broad range of abilities to achieve their full potential.

Selective education was harmful for the national economy. A cascade of official reports over the last 200 years has detailed how English education has failed to keep up with that of its industrial competitors. There never was a time when the national interest was best served by a system that concentrated so much on a minority of pupils, as most of our competitors realised long before we did. This obsession with the academic elite was one of the factors in Britain’s decline.

With the advance of technology and the ever-growing need for a well-educated workforce at every level, the need to have a high standard of education for all, right across the ability range, is greater than ever. All must be part of the quality management system of UK Plc if the country is to survive and prosper.

Far from seeking to reintroduce division at 11, the need is to move towards a more unified system post-16, as the Learning For The Future report from London and Warwick universities demonstrates.

For Conservatives selection has another major disadvantage. It takes away parental choice. For every child who gets a place at a selective school there are many more who do not. Selection gives choice of pupil to some schools, not choice of school to parents. The greater the difference between schools the more unhappy parents are if they do not get their first choice. Selection creates more losers than winners, for if you have grammar schools you also end up with secondary moderns, whatever you call them. This leads to a large number of unhappy parents, to say nothing of unhappy children.

This is something that those pushing for selection by the back door, via grant-maintained schools selecting an ever larger percentage of their intake, should remember. It is profoundly dishonest to pretend that in a selective system you get only winners. If a GM school creams off the brightest and rejects the difficult pupils, that impacts negatively on every other school in the area. It is not acceptable to return to a system that gives advantage to the few at the expense of the many.

Much has been made in the Harriet Harman case of how natural it is for a middle-class mother to want her child to escape from inner-city comprehensives. Some of these, partly reflecting the enormous problems faced by the communities they serve, do not provide a very good education, but creating escape routes for the few is not the solution. What about those who remain?

The only answer is the hard slog of levering up standards in all schools. That is the way to reach the One Nation objective R A Butler had half a century ago - of an education system that meets the social and educational needs of the whole nation.

Demitri Coryton is chairman of the Conservative Education Association TES February 2 1996.