Paul Barker: This is a divided nation ­ within the middle class

On one side are the 'salariat', who've made it; on the other are the 'micro-serfs', tied to computers

Politics and public persuasion work in mysterious ways. The British have become more Thatcherite under the prime ministership of Tony Blair than when she was herself in office. Blair is the Iron Lady's greatest disciple and apostle. This is the paradoxical message from the most authoritative study of changing British attitudes, British Social Attitudes, published today. And he may yet pay a price for this.

In its 20th annual report, the survey looks back over two momentous decades. In 1983, Ronald Reagan was US President, Yuri Andropov was general secretary of the Soviet Communist Party - and Margaret Thatcher was enjoying her post-Falklands heyday. Now we have George Bush Jnr, Vladimir Putin and Blair. But when Mrs T. was at 10 Downing Street, battling (as she saw it) against years of misguided governmental paternalism, the survey shows that her attitudes were seldom shared by the public, in spite of her electoral success.

People's attitudes generally hardened against her line on welfare dependency, her harshness towards the unemployed, her sacrilegious view of the National Health Service. Under her tepid successor, John Major (Thatcher Mark II), the public stance hardly shifted. But under the banner of Tony Blair, Thatcherism won the day. It was a slow-burn triumph for the Great Moving-Right Show.

Blair, on this evidence, is confirmed as Thatcher Mark III. This may yet prove to be his downfall. The survey notes that, for public attitudes, his crucial achievement was to shift his party's stance to the right. The symbolic change was to scrap Clause Four in 1995. He ended up running what many Tories, for the time being, came to feel was the best Conservative government they were likely to get. But, the researchers conclude, by "helping to move the centre ground of public opinion to the right" he could have dug a trap for himself and his party: "He may have just made the Conservatives' chances of regaining power that little bit easier, if and when the public tires of his administration."

The most crucial attitude change is among the people the survey calls "Thatcher's children" - that is, anyone who grew up in the 1980s; roughly, those who're now between about 18 and 35. The public in general, but especially this younger Thatcher-minded segment, has come to place most emphasis on "those parts of the welfare state from which all benefit" - spending on health, education, pensioners and children - and less on assistance targeted at "out-groups" like lone parents and the unemployed, whom an increasingly Thatcherite public opinion perceives as at risk of welfare-dependency.

But bets are hedged. Thatcher's children do not expect that the state will, in practice, keep them in their old age in the manner to which they've become accustomed. Only 16 per cent of this age group expect most of their retirement income to come from the state. Sixty-two per cent expect it will come from an occupational or personal pension; 12 per cent think it will come from savings and investments.

The NHS is the touchstone of change. Throughout these 20 years it has remained much cherished. But attitudes to it don't stand where they did. The NHS is now expected to deliver the goods, hit targets, shorten waiting lists. It's a machine for delivering consumer satisfaction. The survey concludes: "It cannot rely on support for its founding principles: the care it delivers must not only continue to improve but, crucially, be seen to do so." Mrs T. could hardly have put it better.

Consider, finally, attitudes towards Europe. While Mrs Thatcher fought her own anti-Brussels battles, opinion was generally, if vaguely, pro-European. The rows over the Maastricht treaty, and notably over the euro, have changed all that. Only 15 per cent of the public favour leaving the European Union altogether, but 58 per cent wish to reduce the EU's powers or at least leave them where they are. A mere 12 per cent favour increasing Brussels's sway.

Mrs Thatcher was often accused of bringing the attitudes of a shopkeeper to the business of government. The lower-middle class have always been despised by both sides, the established middle class and the working class. Why? Because they are the social zone of transition. But this group, and its attitudes, are precisely the place for trend-watchers to keep an eye on. They have bettered themselves, and they want their children to move up a notch or two more.

In table after table, the survey shows that the coming divide in attitudes in British society is not between the working class and the middle class. It lies within the ever-expanding middle class. On the one side of the battle are the "salariat": those who've made it. On the other side are (in survey language) the lower supervisory, the technical and the self-employed. A more vivid label would be "micro-serfs", those tied to their computers. These are the new lower middle class. Their attitudes increasingly diverge from the salariat. They're tougher and more self-interested. These are the very heartland of Thatcherism, her truest children. And there are more and more of them. Tony Blair set out to woo them, with his imagery of Mondeo Man. But, driving their new VWs or Renaults, they may yet hit-and-run him and his party. They go where the advantage is.

The writer is a senior research fellow at the Institute of Community Studies