Klein introduces the reader to Ewen Cameron, a psychologist at the University of Mcgill who researched the effects of psychological trauma and electro-shock therapy. Whether his original interest was genuinely medical or not, his research in these areas continued as part of a CIA-funded program at many universities and hospitals to develop an understanding of torture techniques, ostensibly to understand the treatment of American POW's in the Vietnam War.
Klein explains that the techniques perfected by Cameron and others of the era formed an important part of the KUBARK manual, essentially the CIA's guidebook to torture. Strikingly similar techniques, including reading KUBARK, have been used from Saigon to Afghanistan to Guantanamo. Klein's point is that they have been used not 'simply' as part of a war effort, but as part of a targeted campaign to quiet unrest and protest that might arise in to changes in regulation, government, and the economy. Throughout her case studies of crises and economic reform, she includes numerous examples of torture, terror, and intimidation measures employed to keep the affected populations quiet.
This opening allows Klein to set up the driving analogy of the book: nations and their people at key moments are just like Cameron's patients during shock treatment: a confused, somewhat blank slate ready for new information. The 'doctor' would be the US government, lent economists, or the World Bank, etc, who minister the shock or crisis as well as the 'healing' therapy afterward – the free market reforms supposedly intended to save the economy. So, the structure of disaster capitalism closely resembles the structure of Cameron’s medieval program of torture and rehabilitation of patients.