Multipolarity

Multipolarity is a distribution of global power among several major states or centers. It contrasts with systems dominated by one state or divided between two.

Balance of power: A condition in which states' capabilities are distributed so that none can dominate the others. States may build coalitions or capabilities to prevent any one pole from gaining supremacy.
Unipolarity: An international system in which one state possesses predominant power. It concentrates system-wide influence in a single leading state rather than several poles.
Congress of Vienna: The 1814–1815 diplomatic settlement that reorganized Europe after Napoleon's defeat. Its settlement sought stability through cooperation among several European great powers.
Power transition theory: A theory linking shifts in relative power between leading states to the risk of major war. It asks whether changing ranks among several powers make multipolar systems especially dangerous.
Alliance: A formal or informal agreement between states to coordinate policy or provide mutual support. Shifting alliances let states counter concentrations of power among rival poles.
Bipolarity: An international system organized around two dominant states or coalitions. It reduces the main strategic competition to two poles.
European balance of power: The changing distribution of influence among European states, especially from the early modern era through the twentieth century. European diplomacy supplies classic cases of competition among several major powers.
Thucydides Trap: The proposed tendency for rising powers to provoke fear and conflict with established powers. Its focus on a rising challenger tests whether multipolarity can become a contest over leadership.
Deterrence: A strategy that seeks to prevent an action by threatening unacceptable costs. Multiple powerful states must signal threats and resolve without misreading one another.
Hegemony: A condition in which one state exercises predominant influence over an international order. A hegemon may organize rules and institutions that constrain the autonomy of other poles.

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