Johann Hari: This is an idiot's version of her masterpiece

Naomi Klein's The Shock Doctrine is one of the most important political books of the past decade. She takes the central myth of the right, "that since the fall of Soviet tyranny, free elections and free markets have skipped hand in hand together towards the shimmering sunset of history", and shows that it is a lie. It is a major revisionist history of the world that Milton Friedman and the market fundamentalists have built.

In the new Depression, with their vision lying in smoking rubble, it is a thesis whose time has come, yet its film, alas, has not. The new "adaptation" of the book by Michael Winterbottom is garbled to the point of meaninglessness.

Klein argues that humans consistently vote for mixed economies, a mix of markets and counterbalancing welfare states. The right has been unable to defeat it in democratic elections. So in order to achieve their vision of "pure capitalism", they have waited for massive crises "when the population is left reeling and unable to object" to impose their vision.

Klein's story begins with the market fundamentalists' show-room: Chile. Milton Friedman, the apostle of pure unfettered capitalism, sent many of his finest students to Chile to spread the message that markets must be allowed to work their pristine logic unhindered by governments. They persuaded nobody. Their parties were defeated, and the democratic socialist Salvador Allende was elected. So when the CIA backed an anti-democratic coup by the fascist general Augusto Pinochet, Friedman stepped in to design "the most extreme capitalist makeover ever attempted anywhere", as Klein puts it.

All subsidies for the poor were scrubbed away, prices were sent soaring and unemployment reached unprecedented levels. The wishes of the people could be safely ignored, because "the shock of the torture chamber terrorised anyone thinking of standing in the way of the economic shocks", she notes. So the right-wing vision of "total markets slice away all social protections and let the corporations rule" was born with the iron fist of state violence as its conjoined twin. Klein tracks this pair from post-Soviet Russia to post-apartheid South Africa to post-tsunami Sri Lanka, showing how they were imposed by the same forces each time.

Klein's account of this "disaster capitalism" is written with a perfectly distilled anger, channelled through hard fact. So what happened to the film? Winterbottom serves up a cold porridge of archive footage and soundbites that have some vague link to the book, without the connecting spine of Klein's explanations. It is as though an idiot has explained the book to another idiot, who then made a film.

This film should have been another Inconvenient Truth. Instead, it's just inconvenient and a shocking waste of a masterpiece.