The struggle of the proletariat against the bourgeoisie must eventually result in the seizure of State power by the proletariat. One would naturally expect this to take place independently in each individual State, and Marx has pointed out that ‘in form, if not in essence, the struggle of the proletariat against the bourgeoisie is primarily a national struggle. The proletariat of every country will abolish its own bourgeoisie.’ However, the matter cannot always be resolved so favourably. The immense strength contained in the State power of the bourgeoisie, the scant probability of a simultaneous revolutionary socialist outburst in several countries at once, and finally the experience the bourgeoisie has gained in its struggle with the working class, force one to acknowlege that a country where the proletariat has taken power into its own hands may for some time remain an isolated socialist island amidst a surrounding sea of bourgeois states.

The outbreak of a socialist revolution in one State will inevitably produce an intensification of bourgeois dictatorship in neighbouring States, and the State where the proletariat has rebelled will immediately become the target for the thunderbolts of the entire bourgeois world. Such conditions give birth to civil war. This initially breaks out on a national scale, although the overthrown bourgeoisie does also receive support for its counter-revolutionary struggle from the world bourgeoisie. The civil war outgrows its national dimensions and develops into a major international class war, as the bourgeois world grows convinced that the defeated bourgeoisie of the country concerned is unable to recover State power; convinced too that the dictatorship of the proletariat, as it consolidates its position, is by its very existence becoming a threat to the tranquillity of world capital.

Thus, from the moment of insurrection, the proletariat joins battle not only with its own bourgeoisie, but also—unequally matched—with the bourgeoisie of the entire world. Thus, as it develops, the struggle between the working class and the bourgeois class ceases to be purely a domestic one, and becomes an international war in which the proletariat cannot restrict itself to a passive role. An attack by a working-class revolutionary army over the boundaries of a neighbouring bourgeois State can overthrow the power of the bourgeoisie there, and transfer dictatorship into the hands of the proletariat.

In general, the seizure of power in a bourgeois country can take place in two ways; firstly by means of a revolutionary uprising of the working class within that country, and secondly by means of armed action on the part of a neighbouring proletarian State. The aim in both these cases is identical—to bring about a socialist revolution. That is why, naturally, they should be considered of equal value, for the workers of all countries.

The basic precondition for the successful seizure of power lies in the readiness of the masses for such a revolutionary take-over. The two determining factors here are the level of development attained by the working class, and—even more important—the hopelessness of all other methods. Hatred divides the workers and the bourgeoisie into two irreconcilable classes, which can no longer avoid a bloody conflict. This awareness of who their class enemies are, together with a consciousness of class solidarity with the workers of the entire world, are the main factors preparing the ground for socialist revolution. A revolution runs into major obstacles if the class instinct of the proletariat is dulled by petit-bourgeois nationalism.

A socialist revolution begins with the seizure of power. Power, once seized, can only be permanently held if the proletariat is already fully prepared for revolution, or else capable of becoming quickly revolutionized and thus of supporting its more audacious and better prepared vanguard. From this point of view, a revolution within a given State has great advantages; beginning most frequently with the seizure of power in the capital, it then spreads out and penetrates deeper into the working masses.

This growth of the revolution, its introduction among the working masses, is an absolute precondition for the success of the communist movement. The encroachment upon a bourgeois system, established over decades and centuries, cannot succeed if the revolution does not stir up the main body of the working people. Only a general revolutionary upheaval, flaring up with the bright light of revolutionary spirit, can create the offensive movement, unrestrainable in its impetuosity and courage, that is necessary for the destruction of the older order and the creation of the new.