The Bolshevik revolution of October 1917 had been led by a small group of dedicated revolutionaries, who believed that the time was ripe for communist revolutions all over the world, not just in Russia. After the First World War there were upheavals in several European countries, during which Soviet style republics were set up in Bavaria (in Germany) and in Hungary. But these were soon crushed. A socialist uprising in Germany was defeated in 1923; therefore Russia was left isolated as the only communist state.

Trotsky, who considered himself Lenin's natural successor, believed in 'permanent revolution'. These were its main aspects:

• Workers' power was the only way forward for backward Russia.
  

• Socialism could not be created in Russia alone because the working class was too tiny and the economy was too backward. It could only be achieved if the large working classes took power in the developed Western countries and shared their resources with communist Russia.
  

• Capitalism was an international system and socialism would be too. To succeed, the resolution hid to spread abroad.

Stalin was a pragmatist. He was not an intellectual, but he realized the importance of ideas in furthering his ambitions. As one historian has written:

Stalin's attitude to ideas was Utilitarian. If they served to make the Soviet Union stronger they were welcome.

Stalin realized that there were unlikely to be socialist revolutions abroad in the near future. His alternative was to be 'socialism in one country'.

We communists are... made of special stuff, he declared. The Soviet Union would create socialism alone. This policy met with approval from the Russian people, who were weary of waiting for revolutions abroad. But in order to survive without support from other countries, the USSR needed to create a strong industrial economy. The peasants, who formed the majority of the population had to be persuaded or forced to abandon their traditional way of life. The way to do this was to introduce state-controlled industrialization.