Here are some snippets from an essay by James Hughes (LSE), published recently in the Routledge Handbook of Ethnic Conflict, and subsequently available online as an e-print:

A persuasive case has been made for the colonial “land grabbing” origins of the modern conception of genocide. A pattern of genocide has emerged historically in places where land greed has become infused with religious bigotry, and where the racist and religious ideologies of coercive colonial conquest combine with settler colonialism (Kiernan, 2007). European philosophers have debated since the Sixteenth century on the morality of colonial occupation and barbarism, including the physical and “cultural” genocides of indigenous societies versus their rights – all conducted under the rubric of the mission civilisatrice (Fitzmaurice, 2008). Historically, settler colonists and the settler colonial mentality of forced acquisition, have been the driving forces for the dehumanization and displacement of peoples, the logical conclusion of which is genocide. The interaction of religion and the interests of settler colonialists is most illuminating when the core elements of both are the basis for an overriding state ideology as in the US ideology of “Providence” and later “Manifest destiny”, and the Zionist Biblically-rooted claims to Palestine. In these and other cases genocidal massacres were employed as a terrorizing land clearing device. While state leaderships have often attempted to disguise the motivations of racism and religious bigotry within the more legitimate ideological wrappings of security or national interests, it is generally only the exceptionally fanatical leader who openly expresses clarity of genocidal intent. Cromwell saw his massacres of the Irish as a “judgement of God” on “Papists”, and the Cromwellian attributed slogan “to Hell or Connaught” captures the logic of his policy. Hitler’s demand for “living space” for Germany in the East was also intended to secure an ideological result – to obliterate “Jewish Bolshevization”. Yet, even great democrats can articulate deeply genocidal instincts. How different the Jefferson Memorial would look if it inscribed his damnation of the native Americans: “to pursue them to extermination”. To be fair to Jefferson, this and a few comments of similar ilk were reluctantly made in the aftermath of massacres of settlers by native Americans, and unlike many of his contemporaries, Jefferson recognized that genocide was part of the “Anglo” culture of colonial occupation, from Ireland to Asia. For some scholars, ethnic competition for land was a factor in the Rwanda genocide, as it is in Darfur. A sole focus on threat perception and security dilemmas, however, distracts us from the role of state ambitions and material interests. Elites may exaggerate a threat and thereby provide a discourse to legitimize acts which may, in fact, have an ulterior motive, whether it is the pursuit of material interests – seizing and colonizing lands from another group; or imposing ideological hegemony – as in racial purity, or counter communism.

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So the question remains what makes some societies genocidal and others not? Much of the scholarship on genocide, generated from the US and informed by liberal norms, is overly focused on the relationship between genocide and twentieth century totalitarian and authoritarian states. As Kuper, Mann and others have argued, genocide affects all historical periods and regimes, including democracies. If we further take into account the role of state strategic ambitions, ideological and material interests, racism, imperialism and settler colonialism, and forms of inequality and group competition we come closer to explaining why state/societal resentments against specific groups can turn genocidal. Ideologies of racial superiority, in particular, however explicit or implicit, are likely to be an important part of the justification for genocide.