Nick Davies’s thesis is simple and it makes for a riveting read. The corrosive effect of child poverty, coupled with Kenneth Baker’s educational reforms of the late Eighties, has produced educational failure on a massive scale.

Lord Baker, living in retirement in an “eye-wateringly beautiful house in one of Sussex’s prettiest villages”, is the first villain of Davies’s piece. He neither understands poverty, Davies argues, nor is he unduly concerned about it. But it is the force of Davies’s attack on David Blunkett which makes this book particularly striking, even shocking.

He claims to have begun his investigation (much of which originally appeared in the guardian) with a “vague feeling of unspecified benevolence”; he has emerged from it “with a feeling close to contempt”.

The reasons for his choosing Sheffield to demonstrate his thesis will not be lost on anyone. For much of the Eighties it was Blunkett’s local government fiefdom. Now, says Davies, it provides in microcosm a picture of what has happened to secondary schools throughout the country. Baker’s reforms made polarisation into rich and poor inevitable. Davies argues that these reforms were all part of a Thatcherite plot to destroy comprehensive schools.

What has happened to Sheffield’s schools over the past 20 years is indeed a sobering story. The impact of the market has been described before but rarely with such force.

The Secretary of State, according to Davies, is wilfully choosing to ignore the obvious: the effect of poverty and the Baker reforms. Instead, he says, we are being offered a “smokescreen of pseudo-solutions”.

Movin south, Davies uses Brighton to demonstrate how the polarisation between schools is exacerbated by the private sector. Roedean and the Stanley Deacon school on a council estate are geographically close. In every other way they are poles apart. This educational and social apartheid is of course familiar but, again, Davies has found a particularly heartbreaking example.

He concludes with a positive proposal - re-examination of vocational education based on a Dutch model.

The fiercest attack on Blunkett is the chapter “The pound;19 billion lie: How Mr Blunkett Fiddled the Figures”. Not only are the statistics pertaining to the extra pound;19 million for education dodgy, Davies claims, but the DfEE’s gloss on what is happening in Fresh Start schools is also highly suspect.

This polemical approach leaves me feeling uneasy. In setting out the grinding nature of life in deprived areas, the author fails to lend the citizens who live there any kind of dignity. They are seen almost wholly as victims; the book would have benefited from some heart-warming stories about those who do succeed despite their circumstances. There is a wholly unnecessary section on cheating in public examinations.

Finally, I cannot accept that Blunkett is quite as cynical as Davies suggests. Politicians will be hamstrung for the foreseeable future by the polarisation of schools. Parental choice is here to stay. Blunkett sent his own children to one of the toughest and most socially deprived schools in an inner-city area. Given this commitment, such a severe slur on his integrity will be seen by many readers as unfair.

Dennis Richards is headteacher of St Aidan’s Church of England high school, Harrogate, North Yorkshire