Vickery's book has been frequently characterised as a 'denial literature' by the right yet the book contains an extensive records of the barbarity of the Khmer Rouge - particularly the Eastern zone massacres of 1978 which left the now well-known mounds of human bones in their wake. Similarly, Vickery praises the overthrow of the Khmer Rouge and argues that the Vietnamese-backed regime which replaced it was a vast improvement for the Cambodian people. This is hardly consistant with the argument that he is a Cambodian 'holocaust denier', and in stark contrast to the US and other western governments (and China) which supported the Khmer Rouge after their overthrow, as chronicled by Vickery in the book's two last chapters.
However, the casualty count of 700'000 - based on CIA data - is too low. Neither does the thesis of a 'peasant revolution' explain the nature of the Khmer Rouge regime. The Pol Pot government was led by a new ruling class drawn from the party, and were fundamentally an urban regime exploiting the Cambodian workers and peasants. This is consistent with other Stalinist regimes but not with Marxism, which states that peasants would be allowed to retain their land until they choose to join co-operatives voluntarily (see Engels' writing on the peasant question). However, all these arguments are within the realm of honest debate without the need for hysterical accusations of holocaust denial.
Where Vickery is right is in characterising the eastern zone as relatively more benign area of Cambodian and as the centre of opposition to Pol Pot. Ben Kiernan in his 1994 history argues the same and praises Vickery's work on this subject (if not others). Also - and part of the book mainly ignored by those on the right - is the book's situation of the Khmer Rouge directly in the history of Cambodia with it's attendent social discontent ,oppression and revolts, in the first chapter, and the vicious US-backed war and bombing in the second (in which more bombs were dropped on Cambodia in six months of 1973 than Japan during all of WW2). This is in contrast to the conservative interpretation that locates the crimes of the Pol Pot solely in Marxism-Leninism.
Vickery's book is a useful antioote to Cold War propaganda but should be read with some caution and alongside more recent works.