A political doctrine and practice born as a banner of counter-revolution in Russia, which asserted that a world revolution was not necessary to "build" socialism and that the Russian state, rechristened the "socialist fatherland", was the main conquest of the universal proletariat.
The main consequence of socialism in one country was the primacy of the international relations of Russian state capitalism over the development of the world revolution, and the unconditional subordination of the International and its various national parties to the defense of the "socialist fatherland".
Socialism in one country in practice
In practice its adoption asserted the interests of the Russian bureaucracy above the world revolution. Once it was imposed on the national parties by the Comintern, these parties paved the way for ever bloodier defeats of the proletariat (Britain in 1926, the handing over of the Chinese revolution to the Kuomintang in 1926-27, Hitler's rise to power in Germany...) until they became the direct organizers of the counter-revolution and of the massacre of the workers in Spain in 1936-37, opening the way to a new imperialist world war in which, after two years of alliance with Germany, they would call for lining up behind the Allied imperialist powers.
The break with internationalism, that is, with the struggle of the world proletariat, was officially marked in the mid-1920s by the hoax of "socialism in one country". It brought with it the Stalinization of the Communist International and the consequent transformation of its parties into organs for the para-military or military defense, as the case may be, of Russia's borders. By natural extension, also into organs of imperialist expansion, since between defense and expansion there stands only a military incident, when not simply a diplomatic one.
The first directly military use of a party took place in China. Shortly after the destruction of the soviets by Chiang Kai-shek and Mao Tse-tung in coalition, Moscow gave the order to launch an undeclared war of harassment against the former, supplying the indispensable logistical support and a protective border. The fundamental method of its foreign policy was established once and for all: first of all keep the proletarian revolution at a distance and, if necessary, crush it; then, direct or indirect military defense of Russian interests.
The abandonment of Germany to Hitler, the Popular Front, the destruction of the Spanish revolution, all belong to this political line, which denies and prevents the struggle of the exploited class in each country and internationally. With the war, this line culminates in the installation of Russia as the second imperialist power, though not without material help from the first. Then the meaning of the foreign policy inaugurated in China is laid bare: rejection of the communist revolution at all costs, as the condition for the free play among imperialist powers.
All the operations mounted by Russia (Korea, Vietnam, Cuba, Bengal, etc.) differ from the military-police intervention in East Berlin, Hungary, Czechoslovakia and Poland not by their nature but by mere geographical accident, by taking place in the American zone. There is strict continuity and completion between Mao Tse-tung's so-called "long march", the crushing of the revolution in Spain and the invasion of Czechoslovakia in 1968.
G. Munis. Party-State, Stalinism, Revolution, 1974