In the 100 years since Lenin’s coup in Russia, the ideology devoted to abolishing markets and private property has left a long, murderous trail of destruction.

A century ago this week, communism took over the Russian empire, the world’s largest state at the time. Leftist movements of various sorts had been common in European politics long before the revolution of Oct. 25, 1917 (which became Nov. 7 in the reformed Russian calendar), but Vladimir Lenin and his Bolsheviks were different. They were not merely fanatical in their convictions but flexible in their tactics—and fortunate in their opponents. Communism entered history as a ferocious yet idealistic condemnation of capitalism, promising a better world. Its adherents, like others on the left, blamed capitalism for the miserable conditions that afflicted peasants and workers alike and for the prevalence of indentured and child labor. Communists saw the slaughter of World War I as a direct result of the rapacious competition among the great powers for overseas markets. But a century of communism in power—with holdouts even now in Cuba, North Korea and China—has made clear the human cost of a political program bent on overthrowing capitalism.

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