The Tragedy of Great Power Politics is a book by the American scholar John Mearsheimer on the subject of international relations theory published by W.W. Norton & Company in 2001. Mearsheimer explains and argues for his theory of "offensive realism" by stating its key assumptions, evolution from early realist theory, and its predictive capability. An article adapted from the book had previously been published by Foreign Affairs.The five bed-rock assumptions of Mearsheimer's theory of offensive realism are: Anarchy: the international system is anarchic; Offensive military capabilities: all great powers possess offensive military capabilities which they can use against each other; Uncertainty: states cannot be sure that other states will not use military capabilities against them; Survival: the primary goal of states is survival; Rationality: States are rational unitary actors who think strategically about how to pursue their primary goal (survival).From these assumptions, Mearsheimer argues that states will constantly seek to accumulate power, and that cooperation between states is hard. The "tragedy" of great power politics is that even security-seeking great powers will nonetheless be forced to engage in competition and conflict with one another. Source: Wikipedia (en)