For those who find the rise of ISIS baffling, much of the past century can only be retrogression from modern life. Even the regime that committed a crime with no precedent in history must be regarded as an example of atavism: the Nazi state has often been described as having taken Europe back to the Dark Ages. Certainly the Nazis exploited a medieval Christian demonology in their persecution and genocide of Jews, but Nazism also invoked a modern pseudoscience of race to legitimate these atrocities. Invoking a type of faux Darwinism, Nazi racism could have emerged only in a time shaped by science. Nazism was modern not just in its methods of killing but also in its way of thinking.
This is not to reiterate the claim—made by Marxian theorists of the Frankfurt School—that modern scientific thinking leads, by some circuitous but inevitable route, to Nazism and the Holocaust. It is to suggest that when it is invoked in politics modernity is a figment. The increase of knowledge in recent centuries is real enough, as is the enlargement of human power through technology. These advances are cumulative and accelerating and, in any realistically likely scenario, practically irreversible. But there have been few, if any, similar advances in politics. The quickening advance of science and technology in the past few centuries has not gone with any comparable advance in civilization or human rationality. Instead, the increase of knowledge has repeatedly interacted with human conflicts and passions to produce new kinds of barbarism.
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