On August 20, 1940, Leon Trotsky was assassinated by an agent of the Soviet secret police, the GPU, in Coyoacán, a suburb of Mexico City, where he was living in exile. Thus ended the life of the great Marxist theoretician of world socialist revolution and one of the towering figures of modern political history.
Trotsky’s assassination ranks among the most politically consequential crimes of the 20th century, with far-reaching implications for the international working class and the world socialist movement. And yet, for decades, the circumstances surrounding the assassination remained shrouded in secrecy. The massive scale of the Stalinist conspiracy against Trotsky was the subject of a carefully orchestrated cover-up.
In 1975, the International Committee of the Fourth International launched the first systematic investigation by the Trotskyist movement into the assassination. This investigation, known as Security and the Fourth International, led to the exposure of the network of GPU and American intelligence agents within the Fourth International that ensured the success of Stalin’s conspiracy against Trotsky’s life and facilitated state surveillance in the decades that followed. The investigation was bitterly opposed by Pabloite and pseudo-left organizations, which denounced the exposure of spies placed inside the Trotskyist movement as “agent-baiting.” This has remained their position, despite the fact that state intelligence documents released following the dissolution of the Soviet Union confirmed the findings of the International Committee and vindicated Security and the Fourth International.