III.

Ideology in and Since the 20th Century

Perhaps the chief distinguishing characteristic of 20th-century ideologies was the almost religious devotion of their adherents to systems of political ideas that were viewed as absolutely incompatible with other systems. This trait has been most pronounced in the two major modern ideologies, communism and fascism. Other political concepts, such as socialism, democracy, and conservatism, while often strongly upheld, have tended to be more diffuse and less exclusive; their proponents differ on some issues while agreeing on others.

The concept of ideology had a profound effect on world civilization in the 20th century. Almost all modern conflicts, from the “crusade against fascism” in World War II to the various “police actions” of the post-war period and today, have had ideological overtones. The prime example of an ideological conflict was the Cold War, in which the principal antagonists (the United States and the Union of Soviet Socialist Republics) waged a political, economic, and psychological struggle for influence in every part of the world.