Tendency to increase military spending parallel to the development of the authoritarian character of the state and the militarization of social life. Although it appears recurrently in different historical periods and modes of production, it emerges as a permanent trend in capitalism with the entry into its imperialist phase.
Militarism is a product of the extreme and simultaneous development of the internal contradictions -class struggle- and external contradictions of a society, it appears in the decadence of the modes of production. In capitalism it already emerges with imperialism and becomes universal with the entry into decadence of the system. It marks social life in all the states although especially in those that because their political apparatus comes from the counterrevolution -stalinism, fascism, etc.- or because they have weaker national capitals, adopted extremely centralized forms of state capitalism
In any case, in all the central countries the defense of militarism, in the form of defense of the strategic character of military production and its weight in the whole of state expenditure, has to be considered also from the logic of accumulation. The military industry was the first sector that, depending completely on the state, allowed the creation of a "productive" destination for capital that would act as a "driving force" for the national capital's rate of profit.
In practice, militarism, on the basis of indirect taxes, acts in both directions: it ensures, at the expense of the normal living conditions of the working class, both the support of the organ of capitalist domination (the standing army) and the creation of a magnificent field of accumulation for capital.
Rosa Luxemburg. The Accumulation of Capital, 1913.