Introduction
Realism constitutes one of the foundational traditions in the study of International Relations, tracing its theoretical lineages from Thucydides, Niccolò Machiavelli, and Thomas Hobbes to 20th-century classical thinkers like Hans Morgenthau and structural theorists like Kenneth Waltz. At its core, the realist paradigm offers a pessimistic, power-centric interpretation of world politics governed by human nature and systemic constraints.
Core Ontological and Structural Assumptions of Realism
Realist theory, across its classical, structural (neorealist), and neoclassical variants, rests on several interconnected assumptions regarding actors, system structure, and state behavior:
- Statism (State as the Primary, Unitary Actor): Realism posits the sovereign state as the pre-eminent and unitary actor in global affairs. Operating within a billiard-ball model, non-state entities, multinational corporations, and international institutions are considered secondary or subordinate to state power and sovereignty.
- Systemic Anarchy: The international system is characterized by structural anarchy, defined not as persistent chaos, but by the absence of an overarching central governing authority possessing a monopoly on legitimate violence.
- Survival as the Paramount National Interest: In an anarchic environment, state survival constitutes the baseline requirement of all foreign policy calculations. All other socio-economic or normative objectives remain secondary to national security and territorial integrity.
- Self-Help System and the Security Dilemma: Because no supra-national authority exists to guarantee protection, states operate within a self-help mechanism. As John Herz conceptualized, one state's defensive quest for security inevitably triggers a security dilemma, heightening insecurity and mutual suspicion in neighboring states.
- National Interest Defined in Terms of Power: As Hans Morgenthau formulated in classical realism, politics is governed by objective laws rooted in human nature, leading states to define interest in terms of power (animus dominandi). In contrast, Kenneth Waltz's structural realism locates the struggle for power not in biology, but in the pressures of the anarchic systemic distribution of capabilities.
- Amoral Statecraft and Raison d'État: Realism decouples universal moral ethics from foreign policy. Under the doctrine of raison d'état (reason of state), leaders are guided by political prudence, national interest, and tangible outcomes rather than abstract ethical tenets.
- Balance of Power as the Equilibrium Mechanism: To prevent the emergence of a regional or global hegemon, states naturally utilize internal balancing (military buildups) and external balancing (alliances) to preserve system equilibrium.
Critical Counterpoints
Constructivist scholars such as Alexander Wendt argue that anarchy is not an objective, immutable condition but rather what states make of it through intersubjective social practices. Similarly, liberal institutionalists demonstrate that multilateral institutions and economic interdependence can mitigate competitive security dynamics.
Conclusion
Despite criticisms regarding its neglect of domestic politics, non-state actors, and ideational norms, the core assumptions of realism retain enduring analytical power in explaining recurring great-power rivalry, military modernization, and balance-of-power contestations in modern geopolitics.