In his column, George Monbiot attacked our work on Bosnia and Rwanda as "genocide denial" and "revisionism" (Left and libertarian right cohabit in the weird world of the genocide belittlers, 14 June). According to Monbiot, "DNA screening" has "identified the corpses of 6,595" Bosnian Muslims from Srebrenica. But DNA does not establish mode or time of death, and the commission investigating these deaths performs its work behind a veil of confidentiality.

In his examination of Srebrenica-related bodies, the forensic pathologist Ljubisa Simic found that in 77% of cases it was either impossible to determine how they died, or death in combat was strongly indicated.

Monbiot quotes disparagingly from the foreword to The Srebrenica Massacre: "It claims that the 8,000 deaths at Srebrenica are 'an unsupportable exaggeration'." He implies that the quote is attributable to Edward Herman, even though it is a 300-page collection with multiple contributors, and a different gentleman wrote the foreword.

Similarly, Monbiot writes that "the book [sic] claims that the market massacres in Sarajevo were carried out by Bosnian Muslim provocateurs". But multiple contributors cite many sources who make this claim, among whom are UN secretary general Boutros Boutros-Ghali, Lord David Owen, General Michael Rose, and the British joint intelligence committee.

Monbiot complains that we place the "Rwandan genocide in inverted commas throughout" our book The Politics of Genocide. But this is because our work reallocates the primary responsibility for the genocide of April-July 1994, away from the standard account's "conspiracy to commit genocide" by "Hutu Power", towards Tutsi leader Paul Kagame and his superior armed forces. We use scare-quotes to designate the version of events that we reject.

Monbiot cites a "long-discredited deniers' claim" that "Paul Kagame's army 'shot down' President Habyarimana's plane", triggering the genocide. But this claim has never been discredited, and we cite many sources for it. One is the Rwanda tribunal's former investigator Michael Hourigan, who in 1997 found three Tutsi "informants" that named "Kagame and members of the RPF in the downing of President Habyarimana's aircraft".

Monbiot takes issue with our claim that the "great majority of deaths were Hutu", and calls this "as straightforward an instance of revisionism as I've ever seen". But Rwanda's 1991 census estimated the Tutsi population at 600,000, and some 300,000 Tutsi survived the violence of 1994. Whether 800,000 or 1 million people perished, the great majority of deaths must have been Hutu. The standard account of the "Rwandan genocide" is monumentally flawed.

We also cite a 1994 US state department memo that Kagame's forces were killing "10,000 or more Hutu civilians per month". And we cite UN reports from 2002 and 2003 about the resource-theft-related carnage that Kagame's forces had extended to the Democratic Republic of the Congo, the first of which estimated "more than 3.5 million excess deaths".

Monbiot once recognised these deaths in the Congo as resulting from "deliberate policy, commissioned and implemented by the [Kagame] government" (The victim's licence: Our fairytale version of Rwanda's genocide has allowed us to overlook new atrocities, 13 April 2004). Odd that he fails to recognise the same ruthless policy by the same Kagame-led killers inside Rwanda from 1990 to 1994.

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