Trotsky seemed the most likely candidate, and was Lenin’s personal favourite. He had many gifts and intellectual brilliance, but had serious weaknesses that stunted his success. Trotsky himself was a Menshevik, and had converted to a Bolshevik, showing his lack of loyalty. He also had a poor sense of judgement. For example, Stalin’s mishandling of the Georgian Affair (Stalin was liable to abuse any power given to him). Trotsky failed to seize his opportunity to undermine Stalin’s position when Lenin was angry with him. Trotsky however, did not attack. Trotsky was a Jew, and Russia had anti-Semitist beliefs ground into its society. His “race” were seen as outsiders. Other party members saw Trotsky as arrogant and dismissive – they respected him but did not feel any affection or loyalty towards him. It was thought that he would be most likely to cause a split in the party.
When, Joseph Stalin came to power, he made the decision to modernise the Soviet economy. He wanted to generate wealth, and therefore improve the quality of life. Russia was behind from the rest of Europe, and Stalin wanted to “prove” that communism actually worked. In 1927, Stalin launched the "revolution from above" by setting two goals for the Soviet Union, rapid industrialisation and collectivisation of agriculture. His aims were to erase all traces of the capitalism and to transform the Soviet Union as quickly as possible into an industrialised and completely socialist state.
Some might say luck played a large role in Stalin gaining power, something his opponents could not prevent. Lenin fell out with Stalin before his death, and his testament was not published. Had it been made public, Lenin’s criticisms of Stalin would be made apparent, as well as those of Trotsky, Zinoviev and Kamenev. Another lucky break for Stalin was Lenin’s condemnation of divisions within the party in 1921. This made it difficult to attack party policies. The charge of “factionalism” provided Stalin with a weapon for resisting challenges to the authority he had begun to exercise.
The structure of the Soviet State also benefited Stalin. It was a highly centralised machine well suited to a dictatorship. Russia had been used to one single leader ruling the state by divine right, the Tsar. Plus, Stalin also became heir to the Lenin Legacy. In the eyes of the communist party, Lenin was seen as a god. His actions and decisions were unchallengeable. This legitimised Stalin’s position.
Most party members approved of Stalin’s different positions on the NEP during the mid to late 1920’s. His concept of “Socialism in One Country” was more attractive than Trotsky’s “Permanent Revolution”. Trotsky’s policy of Permanent Revolution focussed on spreading revolution and heading towards world revolution. On the other hand, Socialism in one country was the name given to the policy that Stalin promoted, and focussed on strengthening the revolution in Russia. This gave the Russians a special historic role and meant that they would not have to go to war.
In conclusion, those that had the skill to oppose Stalin, like Trotsky, didn’t realise how much of a threat was and failed to unite against him. He also had a great deal of luck – Lenin’s criticisms of him in his testament were not made public, and he had the charge of factionalism to use to discredit anyone who opposed him. However, perhaps above all the most important reason was Stalin’s megalomaniac personality, which made him an ideal dictator. Some have commented on his short height, suggesting that he had a tendency to keep himself to himself and was a “loner”. Even the number of executions declined after his death. He was mad, evil and ruthless.