of the RCP(b)", in which he stated that the peasantry would not turn against the socialist system because he believed they had a self-interest in preserving. The contradictions which would arise with the peasantry during the socialist transition, Stalin surmised, could "be overcome by our own efforts". He concluded that the only viable threat to socialism in the Soviet Union was a military intervention. In late 1925, Stalin received a letter from a party official which stated that his position of "Socialism in One Country" was in contradiction with Friedrich Engels own writings on the subject. Stalin countered, stating that Engels' writings 'reflected' "the era of pre-monopoly capitalism, the pre-imperialist era when there were not yet the conditions of an uneven, abrupt development of the capitalist countries." From 1925 onwards, Bukharin began writing extensively on the subject, and in 1926, Stalin wrote On Questions of Leninism, which contained his best-known writings on the subject. Trotsky, with the publishing of Leninism, began countering Bukharin's and Stalin's arguments, claiming that socialism in one country was possible, but only in the short-run, and claimed that without a world revolution it would be impossible to safeguard the Soviet Union from the "restoration of bourgeoisie relations". Zinoviev on the other hand, disagreed with both Trotsky and Bukharin and Stalin, holding instead steadfast to Lenin's own position from 1917 to 1922, and continued to claim that only a defecting form of socialism could be constructed in the Soviet Union without a world revolution. Bukharin, by now, began arguing for the creation of an autarkic economic model, while Trotsky, in contrast, claimed that the Soviet Union had to participate in the international division of labour to develop. In contrast to Trotsky and Bukharin, Stalin did not believe a world revolution was possible, claiming in 1938 that a world revolution was in fact impossible, and claiming that Engels was wrong on the matter. At the 18th Congress, Stalin took the theory to its inevitable conclusion, claiming that the communist mode of production could be conceived in one country. He rationalised this by claiming that the state could exist in a communist society, as long as the Soviet Union was encircled by capitalism. However, surprisingly, with the establishment of socialist regimes in Eastern Europe, Stalin claimed that socialism in one country was only possible in a large country like the Soviet Union, and that the other states, in order