This year marks the centenary of the world-historic events of 1917, which began with the February Revolution in Russia and culminated in October with “ten days that shook the world”—the conquest of political power by the Bolshevik Party under the leadership of Lenin and Trotsky. One hundred years later, the Russian Revolution retains a burning contemporary relevance. All the great issues that motivated that revolutionary struggle — imperialist violence, social inequality, political repression—are present today. The danger of world war,…