Morgenthau, who is known as the modern father of the realist school of thought, argued that "statesmen think and act in terms of interest defined as power" and that the actions of nations as well as individuals are motivated primarily by their self-interest. He rejected the idea that there was "a rational and moral political order, derived from universally valid abstract principles." He said that the real world consisted of "opposing interests and of conflict among them . . . [in which] "moral principles can never be fully realized, but must at best be approximated through the ever temporary balance of interests and the ever present settlement of conflicts."

Realists tend to define the national interest in terms of the territorial security, and freedom from physical attack and foreign interference of their nation. Viotti and Kauppi add that the national interest includes preservation of a nation's economic vitality and prosperity and of certain "core values," including in the case of the United States its political liberties within its territorial limits. The realists agree with the comment of early Secretary of State John Quincy Adams that America "goes not abroad

Waltz, Kenneth N. Theory of International Politics. Reading, MA: Addison-Wesley, 1979.

Kennan, George. Realities of American Foreign Policy. Princeton: Princeton University Press, 1954.

Craig, Gordon A., and Alexander L. George. Force and Statecraft: Diplomatic Problems of Our Time. New York: Oxford University Press, 1983.

Kennan, George. Diplomacy, 1900-1950. Chicago: University of Chicago Press, 1951.

It is difficult to rally public support in a democracy or indeed in any state for a hazily defined concept of national interest. Kissinger says that "whether fighting world wars or local conflicts, American leaders always claimed to be struggling in the name of principle, not interest." World War I was not fought, for example, to prevent German hegemony in the North Atlantic but rather, in Wilson's phrase to 'make the world safe for democracy.' During the Cold War, much of the containment of communism official rhetoric was overblown, but nevertheless people in the West did not have a hard time believing that the Soviet state armed with thermonuclear weapons represented a threat to their security. After the collapse of the Soviet Union, no such clear and present danger existed which could be used as a rallying cry to justify foreign military intervention by the United States. Hence, even though the stakes were fairly high in the Gulf crisis of 1991, control of a good part of the world's supply of crude oil, public opinion polls showed that public support for military action was somewhat shaky. Public interest in foreign policy issues generally has declined.

Morgenthau, Hans. Politics Among Nations: The Struggle for Power and Peace. New