meridian

Concepts · Meridian Research Team

Realism

Power, survival and the structure of an anarchic international system.

Animated diagram: several independent states with no authority above them, drawn as circles beneath an empty dashed ceilingno higher authority

Conceptual diagram, not data.

Realism starts from the observation that there is no world government. In this condition of anarchy, states must ultimately provide for their own security, and power is the currency through which they do so. Classical realists, notably Hans Morgenthau in Politics Among Nations (1948), located the drive for power partly in human nature and in the interests of states defined in terms of power.

Neorealism. Kenneth Waltz's Theory of International Politics (1979) recast realism as a structural theory. For Waltz, what matters is not the character of leaders but the distribution of capabilities across the system. Because states are functionally alike, they differ chiefly in what they can do, and the number of great powers (whether the system is bipolar or multipolar) shapes how stable it is.

Defensive and offensive variants. Defensive realists, drawing on Waltz and on Robert Jervis's work on the security dilemma, argue that states seek enough power to be secure, and that over-expansion tends to provoke balancing coalitions. Offensive realism, set out by John Mearsheimer in The Tragedy of Great Power Politics (2001), holds that uncertainty about others' intentions pushes great powers to maximise relative power, with regional hegemony as the safest position.

Applying it today. Realist analysis directs attention to shifts in relative capability, to alliance formation and to the limits of institutions when great-power interests diverge. A realist reading of the rise in interstate conflict recorded for 2025 would look first at changing power balances rather than at institutional failure. See MER/26/B01, Fewer Peacekeepers, More Wars Between States.

References

  1. Morgenthau, H. J. (1948) Politics Among Nations: The Struggle for Power and Peace. New York: Alfred A. Knopf. https://openlibrary.org/works/OL1218841W
  2. Waltz, K. N. (1979) Theory of International Politics. Reading, MA: Addison-Wesley. https://openlibrary.org/works/OL5490555W
  3. Mearsheimer, J. J. (2001) The Tragedy of Great Power Politics. New York: W. W. Norton. https://openlibrary.org/works/OL4652460W
  4. Jervis, R. (1978) "Cooperation under the Security Dilemma", World Politics, 30(2), 167–214. https://doi.org/10.2307/2009958

Explainers paraphrase the works cited. They do not quote them. Bibliographic details were checked against the linked catalogue or DOI records.