Progressive force

Russia is decidedly a conquering nation, and was so for a century, until the great movement of 1789 called into potent activity an antagonist of formidable nature. We mean the European Revolution, the explosive force of democratic ideas and man’s native thirst for freedom. Since that epoch there have been in reality but two powers on the continent of Europe – Russia and Absolutism, the Revolution and Democracy. For the moment the Revolution seems to be suppressed, but it lives and is feared as deeply as ever. Witness the terror of the reaction at the news of the late rising at Milan. But let Russia get possession of Turkey, and her strength is increased nearly half, and she becomes superior to all the rest of Europe put together. Such an event would be an unspeakable calamity to the revolutionary cause. The maintenance of Turkish independence, or, in case of a possible dissolution of the Ottoman Empire, the arrest of the Russian scheme of annexation, is a matter of the highest moment. In this instance the interests of the revolutionary Democracy and of England go hand in hand. Neither can permit the Tsar to make Constantinople one of his capitals, and we shall find that when driven to the wall, the one will resist him as determinedly as the other.

— Karl Marx, 1853

A progressive force (or revolutionary force, among other labels) is a concept in Marxist and leftist analysis to refer to social classes, political parties, and even states which, in opposition to the forces of reaction, materially foster the development of the productive forces and relations of production, leading ultimately to the conditions for the growth of the revolutionary class and, eventually, a new form of social organization. This is in opposition to imperialism, which tends to concentrate capital in one place and underdevelop the rest of the world. In a capitalist society, the proletariat is the revolutionary class destined to bring about communism, and therefore, progressive forces tend to be in line with the interests of the workers' movement.

In the 19th century, Marx consistently supported British foreign policy as a progressive counter to what he saw as a reactionary Russian Empire, but even more resolutely supported the revolutionary working class in its struggles against the British ruling class. As such, progressive forces constitute hierarchies which help determine which force should be critically supported. Marx and the working class movement at large also considered nationalism, including the bourgeois nationalism of the Romantic era, to be a progressive force because of its ability to overturn the feudal-absolutist monarchies of old Europe. Marx was particularly supportive of Irish and Polish nationalism, viewing them as potentially crippling forces against Great Britain and Russia, Austria-Hungary, and Prussia respectively. In the 20th century, the world communist movement tended to support nationalist movements in imperialist and colonial holdings in order to help overthrow the basis of European economic power.