"... the realization that human nature precludes utopian social arrangements ..."

Murderous Idealism
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"The media's fleeting attention to the momentous events of the late 1980s and early 1990s matched their earlier indifference to communist systems. There is little public awareness of the large-scale atrocities, killings and human rights violations that occurred in communist states, especially compared with awareness of the Holocaust and Nazism (which led to to far fewer deaths)."
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"In the aftermath of the fall of Soviet communism, many Western intellectuals remain convinced that capitalism is the root of all evil. There has been a long tradition of such animosity among Western intellectuals who gave the benefit of doubt or outright sympathy to political systems that denounced the profit motive and proclaimed their commitment to create a more humane and egalitarian society, and unselfish human beings. The failure of communist systems to improve human nature doesn't mean that all such attempts are doomed, but improvements will be modest and are unlikely to be attained by coercion."
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