This is a very carefully researched book which deserves to be read. It not only covers the involvement by doctors in medical killing but also investigates their psychology. For those interested in medical ethics I'm sure it would be worth reading.
The first half of this book charts the historical progression from direct medical killing of those deemed to be 'life unworthy of life' (often mental patients) through to the most complete expression found in Auschwitz. We see how the medical ideal can be twisted by subverting it to the 'higher' ideal of caring for the health of the social organism by surgically removing the 'ailing' parts.
We are presented with the complex factors involved in this process. The religious, visionary component of the 'world blessing' which the Nazi's have to offer and the purported modelling of the SS on the Jesuits. The scientific component with the interest in eugenics and the 'research' which is carried out. Rudolf Hess declared that National Socialism is 'nothing but applied biology.' And the sense in which some of it is just part of the zeitgeist. The author suggests that there was a fear in Germany that they could fall behind work which was being done in the USA on eugenics. In addition there is the sense of humiliation and disintegration which remains from the First World War. There was a widely accepted right-wing theory that Germany hadn't been militarily defeated but had been undermined by strikes in munitions factories which had been orchestrated by Communists and Jews.
From here, the author offers brief biographies and psychological profiles of Ernst B., Josef Mengele and Eduard Wirths before turning his attention to the psychology of genocide.
There is also an examination of how the development of 'professionalism' results in detachment and objectivity - a psychological 'doubling' which the author has shown to be present in each of his case studies. He suggests that this splitting of the psyche is an important factor in leading towards genocide. Not just doctors but any profession would be advised to reflect on the author's message here and to examine to what extent their professionalism compromises their integrity as a human being.
As you may anticipate, there are moments when this book proves upsetting. It is not an easy read. However, I never felt that the unpleasant incidents were recounted in a gratuitous way. It reminded me of Henry Charles Lea's 'A History of the Inquisition of the Middle Ages.' You may wish to try to get hold of Lea's book (3 volumes) to compare and contrast.