In addition to rational choice, utopianism is a current theory that could serve as a starting point for comprehending the onset of genocide. In contrast to rational choice, which provides a social scientific basis, a focus on utopianism would provide an ideological source of genocide as a uniform substratum. This emphasis on ideology is the basis of a recently published well-written comparison of four genocides by Eric Weitz. Focusing on the concept of utopia at the core of genocidal ideologies, Weitz argues for its salience as an explanation of the Soviet, Cambodian, Nazi, and Bosnian atrocities.SOURCE: The Killing Trap: Genocide in the Twentieth Century, by Manus I. Midlarsky (Cambridge U. Press, 2005), pp. 75-76
In considering Weitz's argument, though, it is apparent that the Marxist-Leninist cases are conflated with cases that have entirely different etiologies. The Soviets had an elaborate ideational class-based justification for mass murder, as did the Cambodians, while the Nazi and Bosnian instances were based on ethnoreligious criteria without elaborate justification. Thus, the concept of utopia does not go very far in explaining these latter two cases. The Nazis had utopian visions of a distant past including an ostensibly racially pure Ottonian Germany, while the Communists (Soviets and Cambodians) possessed a rigorous, if deeply flawed, ideational structure that predicted a future free of class oppression and conflict.
The consequences of ethnoreligious hostilities are vastly different from those of overtly political ideation. In the former, complete eradication is most frequently the goal, while in the latter elimination of incorrigible political enemies along with reeducation of the remainder constitutes the core of the governmental program. Victimization rates, therefore, differ substantially, ranging from the approximately 67 percent of Jews murdered in Nazi-targeted areas of Europe to at most 10 percent of the Soviet and Chinese populations, and 20 percent of the Cambodian. Moreover, possibilities for reconstituting cultural and religious life were sharply circumscribed for Jews (and Armenians) after their genocides. Such limitations were much less pronounced in the Soviet and Cambodian instances; contemporary Russia, indeed, has seen a massive Orthodox revival after the earlier decimation of church officials by the Bolsheviks....
Even more problematic in applying utopianism is the Armenian genocide. Neither in their past nor in any realistically conceived future could the Young Turks imagine a state "purified" of other nationalities, so that an ideology justifying mass murder could not be used effectively as motivation. Certainly at the time of the Armenian genocide in 1915–16, the Greeks, who were somewhat more numerous than the Armenians in the Ottoman Empire and even more dominant in its economic life, were not subject to genocide....
Beyond the problem of generalizability, difficult as it is, the concept of utopianism itself certainly is not sufficient to explain genocide as a behavioral category. There have been utopian socialists of every stripe, for example, from cosmopolitans in the nineteenth-century United States and Europe, to more nationalistic ones in the kibbutzim in Israel. Hardly any had advocated, let alone participated in, genocide. In other words, utopianism can just as readily invoke benign, even reclusive, visions (e.g., the Hutterites), where the last thing any of these utopians wanted to do was to kill or even bother other people.
Where utopianism does get into trouble is in its juncture with the state and especially with state power. The conjoining of the two can lead to genocidal consequences, but it is the state that is the driving force behind the utopian vision or whatever related genocidal motivation (e.g., state security) may exist at the moment of decision. Utopian belief is neither necessary nor sufficient for understanding the origins of genocide although, if strongly held, it certainly can provide the ideational basis for genocidal thinking.
UPDATE: In a comment, reader Otto Pohl objects:
The percentages compared between Nazi Germany and the USSR and Cambodia are apples and oranges. The total percentage of people under Nazi rule murdered is quite small compared to the Soviet and Cambodian cases. Why compare a targeted minority in one case, Jews, and ignore it in the Soviet and Cambodian cases? Stalin murdered over a third of the Chechen, Crimean Tatar and Mennonite populations of the USSR. In Cambodia the Khmer Rouge completely eliminated the ethnic Vietnamese population. Very high percentages of Chams and Chinese also perished. Socialist racism was quite real and no less deadly than the Nazi variant.