Greg Palast is a pain in the arse (or "ass", as they say where he comes from), and proud of it. The press release for the investigative reporter's new book boasts that he is "despised by all the right people" in Tony Blair's Whitehall and George Bush's Washington. But then, Palast also manages to irritate some of us who might expect to be more sympathetic to his criticisms of the political and business elite.

Perhaps it would help if Palast didn't present himself quite so self-righteously as the Lone Researcher, almost single-handedly saving the world from sleaze. This book (largely an updated collection of reports published in the Guardian, the Observer and the Washington Post, and shown on BBC's Newsnight and elsewhere) is modestly subtitled "an investigative reporter exposes the truth about globalisation, corporate cons, and high finance fraudsters". This sets the tone for "the truth" that is to come.

In his first chapter, about the US presidential election scandal in Florida, Palast demands: "How did 100,000 US journalists sent to cover the election FAIL to get the vote theft story?" - the unreported truth that he alone has unearthed. His answer is that all those other reporters are "a flock of docile sheep . . . the little lambs of American journalism", shepherded by the likes of Rupert Murdoch. In the final chapter, he attacks all UK journalists as yapping "little puppies", because we shamefully failed to follow up his "Lobbygate" expose of new Labour.

Perhaps some of those other lambs and puppies share my feeling that Palast's stories don't always stand up - and rarely add up to the historic exposes he claims. So his famous Lobbygate investigation actually proved little more than that new Labour lobbyists such as Derek "Dolly" Draper were silly, boastful boys. As one old-school lobbyist tells Palast, if they delivered half of what they promised, "they'd be in jail! Half of Downing Street would be in jail!"

Palast scatters allegations, innuendo, dramatic stats and anonymous quotes, creating a general impression that he has hit on something. Look a little closer, however, and you are often uncertain exactly what. We all know that the presidential vote in Florida was dubious. I am less sure how much more I know after reading Palast's sensationalised account of "Florida's Ethnic Cleansing of the Voter Rolls", in which, for example, the figure "as many as 15 per cent" appears inexplicably transformed into "a minimum of 15 per cent" within a couple of pages.

There is a more profound problem with Palast's work than his use of statistics. He claims to be speaking up for people whose lives are dominated by big business and big politics. Yet his cynical "trust no one" approach can only reinforce the widespread sense of powerlessness in the face of apparently dark forces. For Palast, it seems, there is somebody shady behind every scene, pulling the strings. Scientific research is a propaganda front for the drug companies, industry equals pollution and sweatshops, politics is all corruption and sleaze. You do not have to accept the elite's claims of benevolence to see a problem in all this. Faced with a world apparently so far beyond our control, there is nothing to be done - except, perhaps, to wait for our hero to unearth the Unreported Truth, and then ask the courts for compensation. Tellingly, Palast believes that, in the United States, the right to sue is more important than the right to vote.

For all this book's claims to have dug below the surface, in the end it remains superficial. It reduces the complex relationship between the state and the capitalist economy to a crude question of corporate graft and bribery. So the Nixon administration plotted to overthrow Salvador Allende in Chile because Pepsi wanted it, and Hitler used Jews as slave labour on the orders of Volkswagen. This comic-book critique of the workings of capitalism undermines the impact of Palast's more interesting revelations - such as the grim US record of a private prison firm involved with the new Labour government.

But then, who am I to criticise? Given that I write a column for the Times, anything I say can presumably be dismissed as an apologia for Murdoch. And it could be thought suspicious that this review appears in a magazine owned by Geoffrey Robinson MP, one of Palast's targets. Palast, however, has many admirers at the New Statesman (the esteemed editor of which he calls a "ballsy cat"). Among the many compliments on the dust jacket, the NS columnist Mark Thomas describes the book as "fucking brilliant". If that doesn't convince you not to buy it, I don't know what will.

Mick Hume is the editor of Spiked (www.spiked-online.com)

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