American political scientist and international relations theoretician (1924-2013)
Kenneth Neal Waltz (June 8, 1924 – May 12, 2013) was a member of the faculty at the University of California and Columbia University and one of the most prominent scholars of international relations (IR) of the 20th century. He was one of the founders of neorealism, or structural realism, in international relations theory.
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I am not saying that such a theory cannot be constructed, but only that I cannot see how to do it in any way that might be useful. The decisive point, anyway, is that a macrotheory of international politics would lack the practical implications of macroeconomic theory. National governments can manipulate system-wide economic variables. No agencies with comparable capabilities exist internationally. Who would act on the possibilities of adjustment that a macrotheory of international politics might reveal?
Each state pursues its own interest's, however defined, in ways it judges best. Force is a means of achieving the external ends of states because there exists no consistent, reliable process of reconciling the conflicts of interest that inevitably arise among similar units in a condition of anarchy.