Balance of power and deterrence
How states check one another, and how threats can prevent war.
Conceptual diagram, not data.
Balance of power. Balance-of-power theory holds that when one state or coalition grows dangerously strong, others will tend to counter it. They may do so internally, by building up their own capabilities, or externally, by forming alliances. In Kenneth Waltz's Theory of International Politics (1979), balancing is a recurrent outcome of an anarchic system rather than a deliberate policy that every state chooses. Debates concern whether states balance against power as such or against threat, and when they instead 'bandwagon' with the stronger side.
Conceptual diagram, not data.
Deterrence. Deterrence means persuading an adversary not to act by convincing it that the costs will outweigh the gains. Thomas Schelling's The Strategy of Conflict (1960) and Arms and Influence (1966) treated military power as a means of bargaining. Schelling distinguished deterrence (preventing an action) from compellence (forcing one), and analysed commitment, credibility and the deliberate manipulation of risk. A threat deters only if it is both capable and believed. Deterrence by denial, which makes an attack unlikely to succeed, is distinct from deterrence by punishment, which makes it too costly.
Applying it today. These ideas inform debates on alliance commitments, extended deterrence and the signalling value of force deployments. They also frame a broader question: when the balance shifts or deterrence fails, can collective arrangements such as peace operations still contain the consequences? See MER/26/B01, Fewer Peacekeepers, More Wars Between States.
References
- Waltz, K. N. (1979) Theory of International Politics. Reading, MA: Addison-Wesley. https://openlibrary.org/works/OL5490555W
- Schelling, T. C. (1960) The Strategy of Conflict. Cambridge, MA: Harvard University Press. https://openlibrary.org/works/OL2259845W
- Schelling, T. C. (1966) Arms and Influence. New Haven: Yale University Press. https://openlibrary.org/works/OL2259854W