Lee Randall, The Scotsman, May 21, 2008

Easy, frequent laughter and juddering sentences born of difficult births aren't what I'm expecting from Naomi Klein, author of The Shock Doctrine, a deeply upsetting book that novelist John Le Carré has called "impassioned, hugely informative, wonderfully controversial, and scary as hell".

Klein, a 38-year-old Canadian journalist, author and film-maker based in Toronto, came to our attention in 2000 with No Logo: Taking Aim at the Brand Bullies, an international bestseller attacking the globalisation movement.

She's been called a combative theorist and a polemicist, and while insisting it's not her intention, she polarises people like no one else. Reviews praise her to the skies – one called Shock Doctrine "lucid, calm, impeccably researched, gorgeously readable" – or denigrate her as a confused leftie with weak arguments. Thus I'm warily expecting a lecture, and disarmed by the mixture of strength and sweetness that Klein evinces during our conversation.

The product of four years of research conducted around the globe, aided by input from seven additional researchers and four lawyers, Klein's book is a detailed dissection of the rapacious mindset behind "disaster capitalism": a strategy that systematically exploits disaster and trauma – such as the Asian tsunami or 9/11 – for economic gain.

This Free Market ideology was conceived by Milton Friedman at the University of Chicago. His adherents, known as the Chicago Boys – they include Donald Rumsfeld and Dick Cheney – have gone on to deploy their ideas around the world.

Just before our meeting, the Cato Institute, a Washington-based think tank, denounced Klein's book. How, I wonder, does she handle the critical onslaught. She shrugs it off as mostly name-calling, saying this is the first serious attack. "But the same day they issued that report," she adds, "they had an event in New York City handing out the Milton Friedman Freedom Fighter Award. They are intimately connected with Friedman. They feel he's their hero and they're defending him. It's a difficult time to be them because the ideology that has been so triumphant, that they have sold to the world, is imploding!

"That background paper misrepresents my argument. It says I confuse Free Market Theory with Corporatism. What I say very clearly is that when free market theory is put into practice you get corporatism. You got it in China; you got it in Russia; you got it in Bush's America and in Pinochet's Chile. What I'm dealing with now are the hardcore true believers, who are not unlike the hardcore Trotskyites saying, 'Don't talk about Stalin or Mao or any of the real-world applications of our theory: the problem was that our ideas were not applied strictly enough!'"

I'm not sure how fully I've understood her densely argued work, but I did get the message that greed is the deadliest sin. Because of greed, thousands were "disappeared" in Argentina, people throughout South America were rendered jobless and destitute, countless were tortured and murdered, and cultures destroyed. I found myself thinking: "Chicago School ideas sound like mince, why were they allowed to prevail?"

"They did it by playing on exactly the thing that you said to me, 'I'm not an expert.' What do you mean? It's our life! This idea that how we organise society should be left in the hands of the few is an old idea that we tried to overthrow. The fundamental tenet of democracy is that people are qualified to make decisions about how the nation spends their collective wealth. The history of the Chicago Boys has been to expand the reach of the market into areas that were previously protected, and at the same time to present it as so overly complicated that only a mathematician could possibly understand it.

"When it starts to implode they blame corruption. What's amazing is that you have a Free Market theory that says that greed and self interest are the most powerful forces in the world, and if you liberate those forces then you will have the healthiest possible society, because you'll have rapid growth and everybody else will be helped in the trickle-down. The idea that you could then be surprised that greed is a powerful force that will go mad is a contradiction, because greed is at the centre of their own theory." She laughs at the absurdity of "this cycle of claiming to be surprised by and blaming corruption, whether it's China or Russia or Iraq. 'What's the problem with Iraq? Well, it's not American policy, it's these greedy Iraqis.'"

Previously she's said that left-wing ideas did not fail, they failed to be implemented. Why? "I think the left has implemented …" she begins, before saying, "Look, many left-wing ideas have failed. Authoritarian communism … you asked me whether I can adapt to changing circumstances. I think the left has adapted to deep, deep debilitating…" She stops and starts again. "I mean, my grandparents never recovered after Stalin made a pact with Hitler! I don't think my grandmother ever got over that. But I like to think we learned from that mistake! I'm such a red-diaper baby – well, my father is."

Klein's American parents moved to Canada in protest against the Vietnam War. Her father is a doctor, her mother, a prominent feminist who made the famous 1981 anti-pornography documentary Not a Love Story. Their house must have been a hotbed of radical ideas, I say. When she visibly withers, I offer up my own youthful indoctrination, courtesy of Mommie Dearest, that religion is the opiate of the people. Klein brightens. "That was one of the first essays I wrote at school! And my theology teacher was a priest, and he gave me a 90!" Mutual giggling ensues.

"My grandparents were quite defeated by their political experiences. My grandfather (an animator at Disney] was fired for union organising and blacklisted. He lost that battle." There's a big pause and lots of stammering. "My grandparents were hardcore Marxists, of that generation who really saw their ideas put into practice, and the devastating results. My grandfather's brother was one of the very few Americans that emigrated to Russia! The betrayal of the Soviet Union was very alive in my family, and it's why I am so committed to democracy.

"My grandfather was so anti-religion that, just to annoy my mother – he was my father's father – he'd cross himself before entering whenever he saw the mezuzah on the door. My mother is not religious, but she had mezuzahs and would have Shabbat dinner. My father was much more anti-religion, but he's softened somewhat. I grew up in a family where my father would torment my mother by bringing home bagels on Yom Kippur (the day of atonement and fasting]!"

Despite a lifelong interest in social justice, Klein went through a label-mad period. "I was just a child of the 80s, I wanted to be an ordinary teenager. It wasn't that spectacular a rebellion, but I had an aversion to activist culture."

Does she really dislike protest marches? "It's true. I've certainly had transcendent movements at protests and concerts, but I think what I don't like is the chanting! And I don't like holding signs. I think it's because communication is my thing, and I don't like other people's slogans."

Has Shock Doctrine made a difference? She's received e-mails from Burma activists. "One has just written a piece about how the Shock Doctrine could be applied in Burma, what the agenda of the Junta is, and how they try to give contracts to cronies. That is interesting, because it's being called out before or while it's happening. These are strategies that rely on being pushed through in that window of opportunity when everyone is concentrated on everything else.""

Finally, I ask her something a friend recently mooted to me: is there any chance we'll ever see the likes of Bush and Rumsfeld tried as war criminals? "Um yes, I think so. Part of it has to do with my spending time in Argentina. When I first went, the military had total immunity. And in about six years, it's been incredible to watch the trials happen and prosecutions for stolen children. So I've seen first hand where there was intractable impunity, and that changed. I don't think we can accept the idea that that doesn't apply to the US.