"But whatever it calls itself - Nazism, Marxist-Leninism, today, terrorism - they all have one thing in common: the destruction, the end of human liberty."
Actually, evil never "calls itself" anything. Those who do evil tend to think they're doing what is necessary and do it in good conscience.
And human liberty tends not to be destroyed, so much as lost through indifference.
Harper's right on one thing, though - it does tend to reinvent itself.