On August 20, 1940, Leon Trotsky invited a man he knew only as Jacques Mornard into his study. Mornard waited for Trotsky to sit, then smashed an ice pick he had hidden in his raincoat into Trotsky’s skull. For over a decade, Trotsky’s greatest enemy, Joseph Stalin, had been trying to arrange his murder. Stalin’s agents had hunted him across Europe and into a lonely, bitter exile in Mexico. He...

In the United States, democracy is under attack by an authoritarian movement that has found fertile ground among the country’s conservative politicians and voters, but similar movements have found homes in the hearts and minds of people around the globe. To understand the shape, form, and stakes of this assault, we must go back to extract lessons from our past.