Figure 6.24 Heartland versus rimland in Eurasia. For most of the twentieth century, the heartland, epitomized by the Soviet Union and communism, was seen as a threat to America and the rest of the world, a notion based originally on the environmental deterministic theory of the political geographer Halford Mackinder. Control of the East European Plain would permit rule of the entire heartland, which, in turn, would be the territorial base for world conquest. During the cold war, 1945 to 1990, the United States and its rimland allies sought to counter this perceived menace by a policy of containment—resisting every expansionist attempt by the heartland powers. (Sources: Mackinder, 1904; Spykman, 1944.)