The book, Imperial Life in the Emerald City, by Rajiv Chandrasekaran, a former Washington Post bureau chief in Baghdad, also states that Baghdad's new traffic regulations after the CPA took charge were based on the state of Maryland's laws, downloaded by an aide. Another book on the six-title shortlist deals with the troubled origins of Iraq. A third is a study of an Islamist extremist murder in Holland.
These harsh themes have elbowed out the gentler arts of literary biography from the climactic stages of the contest. Biographies by two outstanding practitioners, Claire Tomalin's Thomas Hardy, The Time-Torn Man, and Hermione Lee's study of Edith Wharton, might have been favourites in a less political year.
Chandrasekaran's book is based on hundreds of interviews and internal documents within the protected, "Oz-like" Green Zone, inside which the CPA under Paul Bremer tried to rule Iraq in the first year after Saddam's overthrow.
The book says people with Middle Eastern experience were excluded in favour of Republican party loyalists. The New York Times compared the book's chilling effect to the impact of Graham Greene's Vietnam novel The Quiet American.
Georgina Howell's Daughter of the Desert is the biography of Gertrude Bell, the pioneering woman Oxford graduate, mountaineer and archaeologist-spy who travelled from Delhi to the then Mesopotamian front line, took up the causes of an autonomous Arab state and King Faisal and helped to draw Iraq's borders.
Ian Buruma's Murder in Amsterdam is about the killing of the provocative columnist and filmmaker Theo van Gogh by the son of Moroccan immigrants who was angry because he had collaborated with an anti-Islamic politician.
The other shortlisted titles are: Having It So Good: Britain in the Fifties, by Peter Hennessy; Brainwash, by Dominic Streatfeild; and The Verneys, by Adrian Tinniswood. The chair of judges, barrister and peer Helena Kennedy, said: "These are six challenging and extremely well written books which reflect the ideas and spirit of the society we live in. The list helps to bring an understanding of our world at a crucial time in history." Other judges are theoretical nuclear physicist and broadcaster Jim Al-Khalili; writer and editor Diana Athill; historian Tristram Hunt; and journalist and broadcaster Mark Lawson. The winner will be declared on June 18.
The six titles
Murder in Amsterdam, Ian Buruma (Atlantic Books)
Imperial Life in the Emerald City, Rajiv Chandrasekaran (Bloomsbury)
Having it so Good: Britain in the Fifties, Peter Hennessy (Allen Lane)
Daughter of the Desert, Georgina Howell (Pan Macmillan)
Brainwash, Dominic Streatfeild (Hodder & Stoughton)
The Verneys, Adrian Tinniswood (Jonathan Cape)