After Lenin, Trotsky was the most important leader of the Bolshevik revolution of 1917. A hero to the Russian masses, he had decided views about communist strategy, and was later fiercely opposed to Stalin’s tyranny. Stalin had sabotaged the workers’ revolution, Trotsky claimed, by confining it to one country; he was “an outstanding mediocrity”. In August 1940, Trotsky was hunted down in his Mexican exile and eliminated by a Stalinist agent. Thus the monster he helped to create — the Soviet Union — destroyed him.

The first attempt on his life occurred on the morning of May 24, 1940. A group of 20 armed Stalinists stormed his house on the outskirts of Mexico City, disarmed the bodyguards and for 20 minutes machine-gunned, then threw grenades at the property. Trotsky and his wife Natalia survived by huddling under their bed; a bullet fired at their sleeping grandson passed through his mattress and merely grazed him. Miraculously, Trotsky received no more than scratches to his face from flying glass; next time it would be the blunt end of an ice pick.

Stalin’s Nemesis, by the American historian Bertrand Patenaude, is an absorbing reconstruction of Trotsky’s last years in Mexico, where he arrived in 1937 after exile in Turkey and elsewhere in Europe. The purpose of the May 24 raid, says Patenaude, was not just murder but arson. The bullets were intended for Trotsky; the incendiary bombs for his personal papers, which contained damaging allegations about the Great Terror of 1937-38, when anyone who had threatened the Soviet Union by so much as his thoughts, Stalin decreed, had to be liquidated. Some 2m “enemies of the people” perished during that period.

Mexico in the 1930s became an asylum for anti-Stalinists. President Cardenas, the Mexican leader, had confiscated petroleum reserves from British and American companies and, keen to establish Mexico as a haven for political refugees, welcomed Trotsky there. Eight years earlier, the Russian had been hounded out of the Soviet Union, having publicly branded Stalin “the gravedigger of the revolution”. The dictator never forgave him.

Trotsky came under the protection of Mexico’s most famous left-wing artist, Diego Rivera. Rivera’s Mexico City murals, with their Soviet-style depiction of a happy Mexican peasantry, captivated Trotsky. One of them, World War, depicted him in his role as de facto commander of the Red Army, wild-eyed and prophetic.

However, Rivera quickly grew tired of Trotsky’s rigid ideology and mocking humour. The friendship deteriorated further when Rivera’s wife, the smoulderingly handsome painter Frida Kahlo, began an affair with Trotsky. “Little Goatee”, she called him, after his pointed beard. Rivera, a revolver-toting tough, wanted blood. Later he claimed he had lured Trotsky to Mexico with the intention of having him assassinated all along.

Trotsky’s assassin, Ramon Mercader, was a Stalinist Spaniard, who arrived in Mexico City in the summer of 1940. Passing himself off as a Belgian-born Trotskyite under the alias of Jacques ­Mornard, he quickly infiltrated the Trotsky circle. On August 20, Trotsky was at work in his study when Mercader-Mornard asked him if he would read over some political tracts he had written. Trotsky agreed, and as he leant over the material he was struck on the front of the head with the pick. He bellowed in pain yet managed to struggle to his feet, fending off his assailant before collapsing. His bodyguards hurried in and beat up the intruder.

Rushed to hospital, Trotsky died the next day. His assassin was jailed for 20 years by the Mexican authorities. On his release in 1960 he went to live in Moscow, where the Khrushchev regime declared him a hero. Patenaude’s hybrid of history and detective story grips from start to finish. With rare narrative verve, he chronicles the last years of a revolutionary’s life, with its sexual jealousies, paranoia and finally murder. “Death solves all problems,” Stalin had declared. “No man, no problem.”

Stalin’s Nemesis: The Exile and Murder of Leon Trotsky by Bertrand M Patenaude

Faber £20 pp340

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