The balance of power is perhaps the most enduring concept in the study of international relations. At its core, it holds that states will act to prevent any single power from achieving dominance—because a hegemon, unchecked, could threaten the independence of all others.
This principle has guided statecraft for centuries, from the Peace of Westphalia to the Cold War to contemporary debates about the rise of China.
The Basic Logic¶
The balance of power rests on several assumptions:
States seek survival: Above all else, states want to preserve their independence and territorial integrity. This is the foundational assumption of realism in international relations theory.
Power is relative: A state’s security depends not only on its own capabilities but on how those capabilities compare to potential adversaries. An army of 100,000 is strong or weak depending on what the neighbors can muster.
Concentrated power threatens others: A state powerful enough to dominate the system has the capability to threaten others, even if it lacks the immediate intention. Prudent statesmen do not bet survival on the goodwill of the powerful.
Balancing is the natural response: When one state grows too strong, others will combine against it—either by building up their own power (internal balancing) or by forming alliances (external balancing).
The result, in theory, is an equilibrium: no state achieves dominance, and the system persists in a condition of competitive coexistence.
Historical Practice¶
The European System¶
The classic laboratory for balance-of-power politics was early modern Europe. After the Peace of Westphalia (1648), the continent settled into a system of sovereign states with no overarching authority. The major powers—France, Britain, Austria, Prussia, Russia—engaged in constant competition.
Britain as the balancer: For centuries, Britain pursued a deliberate balance-of-power strategy. As an island nation, it had the luxury of choosing when and how to intervene on the continent. British policy consistently opposed whichever power threatened to dominate: Spain in the 16th century, France under Louis XIV and Napoleon, Germany in the 20th century.
The Concert of Europe: After Napoleon’s defeat, the great powers established the Concert of Europe—a loose arrangement for managing conflicts and preventing any state from again bidding for hegemony. The system preserved relative peace from 1815 to 1914, though it ultimately failed to prevent World War I.
The Cold War¶
The bipolar structure of the Cold War represented balance of power in its starkest form. The United States and Soviet Union divided the world into spheres of influence, each deterring the other with nuclear weapons and alliance networks.
The balance was maintained by:
- Nuclear deterrence: Neither side could attack the other without risking annihilation
- Alliance systems: NATO and the Warsaw Pact aggregated power on each side
- Proxy competition: Rather than direct confrontation, the superpowers competed through allies and client states
Varieties of Balance¶
Political scientists distinguish several forms:
Simple balance: Two powers of roughly equal strength check each other (the Cold War model)
Complex balance: Multiple powers of varying strength form shifting coalitions (18th-century Europe)
Regional balance: Equilibrium at the regional level, with external powers sometimes intervening (the Middle East, South Asia)
Offshore balancing: A powerful state remains aloof from regional competition, intervening only when a potential hegemon emerges (British and arguably American strategy)
Mechanisms of Balancing¶
Internal Balancing¶
States can build up their own capabilities:
- Expanding military forces
- Developing new weapons technologies
- Strengthening economic foundations of power
- Mobilizing population for war
Internal balancing is slow but reliable—a state controls its own resources and does not depend on the uncertain commitments of allies.
External Balancing¶
States can aggregate power through alliances:
- Forming defensive pacts
- Extending security guarantees
- Coordinating military planning
- Pooling economic resources
External balancing is faster than internal buildup but carries risks. Allies may defect, free-ride, or drag each other into unwanted conflicts.
Bandwagoning: The Alternative¶
Not all states balance against rising powers. Some bandwagon—they align with the stronger side rather than against it.
Bandwagoning may occur when:
- A state is too weak to balance effectively
- Ideological affinity favors alignment with the rising power
- Geographic exposure makes resistance futile
- The rising power offers inducements to join rather than resist
The debate between balancing and bandwagoning is central to contemporary analysis of how states respond to China’s rise.
Criticisms of Balance of Power¶
Theoretical Problems¶
Ambiguity: What exactly must be balanced? Military power? Economic capacity? Some overall index of “national power”? The concept is notoriously imprecise.
When does balancing occur?: States often delay balancing until threats become acute—by which time it may be too late. Nazi Germany was allowed to grow powerful before effective resistance formed.
Domestic politics matters: The balance-of-power framework assumes states respond rationally to external threats. In practice, domestic ideologies, regime interests, and leadership psychology shape foreign policy.
Empirical Problems¶
Balancing failure: History is littered with cases where balancing failed or never occurred:
- The Greek city-states failed to unite against Macedon
- The Italian states failed to balance against France in the 16th century
- Interwar Europe failed to balance effectively against Germany until 1939
Unipolarity: After the Cold War, the United States enjoyed unprecedented dominance. Balance-of-power theory predicted that other states would combine against American hegemony. Decades later, no effective counterbalancing coalition has emerged—though some argue this is now changing.
Contemporary Applications¶
The Rise of China¶
The most consequential balance-of-power question today concerns China’s ascent:
- Will regional powers (Japan, India, Vietnam, Australia) balance against Beijing?
- Will the United States commit to an offshore balancing strategy in Asia?
- Will China’s neighbors bandwagon rather than resist?
- Can a Sino-American competition remain a stable balance, or will it devolve into conflict?
Different answers to these questions yield radically different expectations about the future.
The Russia Question¶
Russia’s invasion of Ukraine in 2022 triggered a classical balancing response:
- NATO expanded to include Finland and Sweden
- European states increased defense spending
- Sanctions aggregated economic pressure against Moscow
- Military aid flowed to Ukraine
Whether this balancing is sufficient—and sustainable—remains to be seen.
Multipolarity¶
Many analysts argue the world is transitioning from American unipolarity to a multipolar system featuring the US, China, and perhaps the EU, Russia, and India as major poles. If so, balance-of-power dynamics will likely intensify, with shifting alignments and increased competition.
The Moral Dimension¶
Balance-of-power politics has always attracted criticism on ethical grounds:
- It treats states as amoral units seeking only power and survival
- It justifies alliances with unsavory regimes if they serve the balance
- It may perpetuate conflict by assuming competition is inevitable
- It can become a self-fulfilling prophecy—states that assume others are threats may provoke the very hostility they fear
Defenders argue that the balance of power, for all its flaws, has prevented the worst outcome: universal empire under a single dominating power. The competitive state system, with all its wars and rivalries, has also enabled diversity, liberty, and progress in ways a world empire might not.
Conclusion¶
The balance of power is not a law of nature. States do not automatically balance against rising powers, and when they do, they often do so too late or ineffectively. The concept is better understood as a recurring pattern and a strategic framework than as an iron law.
Yet the logic of the balance endures because its foundational premise endures: in a world without a global sovereign, states must look to their own security, and concentrated power is inherently threatening to those who do not possess it.
Understanding balance-of-power thinking is essential for interpreting contemporary geopolitics—and for recognizing both its insights and its limitations.