Anne Applebaum: 100 years later, Bolshevism is back. And we should be worried.

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At the beginning of 1917, on the eve of the Russian revolution, most of the men who later became known to the world as the Bolsheviks were conspirators and fantasists on the margins of society. By the end of the year, they ran Russia. Fringe figures and eccentric movements cannot be counted out. If a system becomes weak enough and the opposition divided enough, if the ruling order is corrupt enough and people are angry enough, extremists can suddenly step into the center, where no one expects them.
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