what was joseph stalins main goal for the soviet union apex
He introduced the first five-year plan for building a socialist economy. In place of the internationalism expressed by Lenin throughout the Revolution, it aimed to build Socialism in One Country.
Soviet Union

In 1928, Stalin introduced the first five-year plan for building a socialist economy. In place of the internationalism expressed by Lenin throughout the Revolution, it aimed to build Socialism in One Country. In industry, the state assumed control over all existing enterprises and undertook an intensive program of industrialization. In agriculture, rather than adhering to the "lead by example" policy advocated by Lenin, forced collectivization of farms was implemented all over the country.

Famines ensued as a result, causing deaths estimated at three to seven million; surviving kulaks were persecuted, and many were sent to Gulags to do forced labor. Social upheaval continued in the mid-1930s. Despite the turmoil of the mid-to-late 1930s, the country developed a robust industrial economy in the years preceding World War II.
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Soviet Union [SEP] Stalin era (1927–1953)
On 3 April 1922, Stalin was named the General Secretary of the Communist Party of the Soviet Union. Lenin had appointed Stalin the head of the Workers' and Peasants' Inspectorate, which gave Stalin considerable power. By gradually consolidating his influence and isolating and outmanoeuvring his rivals within the party, Stalin became the undisputed leader of the country and, by the end of the 1920s, established a totalitarian rule. In October 1927, Zinoviev and Leon Trotsky were expelled from the Central Committee and forced into exile. In 1928, Stalin introduced the first five-year plan for building a socialist economy. In place of the internationalism expressed by Lenin throughout the Revolution, it aimed to build Socialism in One Country.