Trotsky thought that Communism could not survive in the USSR alone. He argued that the capitalist countries of the West feared Communism and would try to destroy it. For this reason, he said, it was necessary to spread Communism to the countries of Western Europe and to their overseas colonies. This would be done by giving help to revolutionary groups and parties in Western Europe.

Stalin put forward an opposite theory - the theory of Socialism in One Country. He argued that the USSR must always come first in the government's plans. The rest of the world must take second place. The Communists should concentrate on building up the economy of the USSR, not waste money on helping revolutionary groups abroad. With a strong, modern and prosperous economy, the capitalist countries would never dare to attack the USSR.

Trotsky's theory was not popular among Party members. the Russians had set up an organisation to help revolutionaries in other countries back in 1919. Its name was Comintern, short for Communist International. Comintern had already backed several attempts at revolution in European countries over the past five years, and all had failed. Trotsky's theory therefore looked unworkable. Faced with mounting criticism from Party members, he resigned from his government post as Commissar for War in 1925.

Stalin Attacks the Left Wing

During his argument with Trotsky, Stalin joined forces with the Rightists - Bukharin, Rykov and Tomsky - who wanted to continue Lenin's New Economic Policy. Stalin joined them not because he agreed with NEP but because he hoped they would help him to drive Trotsky, Zinoviev and Kamenev out of the Politburo.

Sure enough, with the help of the Rightists, Stalin made sure that Trotsky was always voted down in the Politburo. He also arranged for his supporters to vote against Trotsky in meetings of the Party Central Committee. He even saw to it that his supporters booed Trotsky's supporters in public meetings.

At the end of 1925 Stalin's position was strengthened when the Party Congress elected three of his old friends to the Politburo. With their help, Stalin was able to secure the dismissal of Trotsky, Kamenev and Zinoviev from the Politburo. In 1927 Trotsky and Zinoviev were also expelled from the Party.

Stalin Attacks the Right Wing

Now that Stalin had got rid of Trotsky and his supporters, he turned against the Rightists who wanted to continue with NEP. In 1928 Stalin argued in favour of ending NEP and expanding industry as fast as possible. Bukharin and the Rightists tried to argue against him. But now that Stalin had a majority of supporters in the Politburo, their arguments fell on deaf cars. At the start of 1929, Bukharin, Rykov and Tomsky resigned from the Politburo.

Meanwhile, in 1928, Trotsky had been deported to Alma Ata in Soviet Central Asia, and in 1929 he was exiled from the USSR altogether. Stalin was now supreme leader of the USSR.

The Assassination of Trotsky

Trotsky, however, had not heard the last of the argument, for Stalin was determined to wipe him out of political life altogether - wherever he was. While Trotsky went to live in Turkey, and then in France and finally in Mexico, Stalin made sure that all traces of his life in the USSR were wiped out. Trotsky's name was removed from all official publications and photographs of him were destroyed. As we shall see, his supporters in the USSR were purged from the Party and, in many cases, imprisoned or killed.

Finally, in 1940, the NKVD - the secret police - arranged for Trotsky to be murdered. Posing as a supporter of Trotsky, one of their agents talked his way into Trotsky's heavily guarded house, pulled out an ice-axe from beneath his coat and buried its point in Trotsky's skull. Trotsky died of his wounds a day later, on 21 August 1940.