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Irregular warfare (IW) has re-emerged as the dominant mode of great-power competition in the twenty-first century, driven by accelerating globalization, digital hyperconnectivity, and the strategic behavior of revisionist states seeking advantage below the threshold of open armed conflict. Unlike conventional warfare, IW is not defined by decisive battles or territorial conquest. Instead, it is characterized by persistent, ambiguous, and multidomain competition designed to shape political environments, economic systems, social cohesion, and institutional legitimacy over time.
Modern irregular warfare operates across political, informational, military, economic, financial, intelligence, legal, and cyber domains and relies on whole-of-government—and often whole-of-society—mechanisms of influence. These activities are frequently cumulative rather than decisive, producing strategic effects through persistence and integration rather than shock or annihilation. While irregular warfare draws on historical traditions of political warfare, insurgency, and revolutionary struggle, its contemporary form is far more diffuse, transnational, and system-oriented.
The U.S. Department of Defense defines irregular warfare as a form of warfare in which state and non-state actors campaign to assure or coerce other actors through indirect, non-attributable, or asymmetric activities. This definition reflects the reality that modern strategic competition often avoids overt violence while still producing outcomes traditionally associated with war, including territorial change, political realignment, and the erosion of political solidarity or sovereignty.
Understanding this environment requires analytical frameworks that illuminate not only individual instruments of power but also the operational logic that integrates them. The 1983 edition of U.S. Army’s FM 100-5 Operations provided a compact framework for conceptualizing relative combat power through firepower, protection, maneuver, and leadership. While designed for kinetic conflict, the underlying logic of FM 100-5 remains analytically useful if adapted to the conditions of irregular warfare.
This article proposes a modernized framework for irregular warfare consisting of four interrelated components: offense, defense, virtual reach, and leadership. These elements parallel the original FM 100-5 construct while better capturing the tools and logics of contemporary grey-zone competition. Information is treated not as a standalone pillar but as a cross-cutting enabler that shapes perception, attribution, and cognitive terrain across all domains and components in the model.
Offense in Irregular Warfare
Offense in irregular warfare represents the coordinated and proactive use of political, informational, economic, financial, intelligence, cyber, and legal instruments to impose costs, seize initiative, and condition adversary decision-making without resort to conventional military force. As the irregular analogue to firepower, offensive action seeks strategic disruption, coercive leverage, and positional advantage through influence rather than physical destruction.
Economic statecraft constitutes a primary engine of irregular offense. Debt leverage, infrastructure investment, standards-setting, supply-chain manipulation, and alternative financial systems allow states to embed themselves within the economic fabric of partner or target states. These mechanisms generate long-term dependencies that can be activated during crises, often without overt coercion or military presence.
Information and cognitive offense targets trust, identity, and perception. Disinformation campaigns, narrative saturation, media co-optation, and elite capture seek to fracture social cohesion, undermine democratic legitimacy, and distort public decision-making. Because these operations exploit open information environments, they can degrade political resilience and impact decision making in ways that kinetic force cannot.
Cyber operations further expand offensive reach by enabling low-cost, deniable access to adversary networks. Cyber tools facilitate intellectual property theft, infrastructure intrusion, data manipulation, and supply-chain compromise while complicating attribution and retaliation. Cyber offense often supports other irregular instruments by providing sensitive information, coercive leverage, or latent access.
Lawfare—the strategic exploitation of legal systems and norms—has emerged as a central offensive modality. Strategic litigation, selective treaty interpretation, and norm manipulation allow states to legitimize revisionist claims, constrain adversary responses, and reshape international legal baselines over time. Diplomatic pressure campaigns and alliance manipulation reinforce these effects by isolating adversaries politically.
Defense and Resilience in Irregular Warfare
Defense in irregular warfare extends the classical concept of protection beyond physical survivability to emphasize societal, institutional, economic, legal, and cyber resilience. Rather than shielding forces from kinetic attack, irregular defense focuses on preserving strategic autonomy under persistent sub-threshold pressure.
Cognitive security is foundational. Adversaries target public opinion, trust, and identity through coordinated information operations designed to polarize societies and erode confidence in institutions. Effective defense requires media literacy, transparent government communication, independent journalism, and strong civil society to inoculate populations against manipulation.
Economic defense addresses vulnerabilities created by weaponized interdependence. Supply-chain diversification, investment screening, financial transparency, and protection of critical infrastructure reduce exposure to coercive economic practices. Economic resilience underpins political independence and limits adversarial leverage.
Cyber defense protects what has been described as the fifth domain of conflict. Continuous monitoring, rapid response, public–private cooperation, redundancy, and workforce development are essential to mitigate cyber intrusions that enable broader irregular effects.
Legal defense, or counter-lawfare, requires sustained investment in legal expertise and alliance coordination. States must contest unlawful claims in international forums, harmonize legal positions with partners, and defend rule-of-law norms to prevent the normalization of revisionist interpretations.
Virtual Reach and Maneuver in the Grey Zone
Virtual reach represents the irregular analogue to maneuver. Instead of repositioning forces in physical space, states maneuver through cyberspace, financial systems, infrastructure networks, supply chains, international institutions, and maritime grey zones. Positional advantage is gained by shaping systems and perceptions rather than seizing territory.
Cyberspace offers the most agile maneuver environment. Persistent reconnaissance, network penetration, and prepositioned access allow states to influence adversary systems at distance while remaining below escalation thresholds.
Infrastructure and economic networks function as maneuver corridors. Control of ports, railways, telecommunications, and payment systems enables states to restructure regional connectivity and generate political leverage without military deployment.
Narrative maneuver seeks dominance over interpretive terrain. In the cognitive domain, agenda-setting, narrative flooding, and cultural influence shape perceptions of legality, legitimacy, and responsibility, often determining political outcomes before material power is applied.
Maritime grey zones combine ambiguity, gradualism, and legal layering to advance territorial claims without triggering armed conflict. The cumulative normalization of such actions exemplifies irregular maneuver in practice.
Leadership as Strategic Integration—An Imperative
Leadership is the decisive integrative element of irregular warfare. Just as FM 100-5 emphasized leadership as central to relative combat power, effective IW leadership synchronizes offense, defense, and virtual reach operationally under coherent strategic intent.
Leadership in irregular warfare requires long-term vision, whole-of-government coordination, narrative discipline, and sustained legitimacy. Without integration, irregular efforts fragment into reactive actions that fail to produce cumulative advantage.
Narrative leadership is particularly critical. Strategic narratives justify state behavior, mobilize domestic support, and shape international perceptions. States that lose narrative coherence often cede legitimacy even when material capabilities remain strong.
Case Study: China as a Skilled Irregular Warfare Actor
China provides a contemporary example of integrated irregular warfare. Beijing employs economic statecraft—buying influence; cyber operations; cognitive influence—aggressively seeking to alter perceptions offensively and defensively; and, lawfare within a coherent strategic framework. Belt and Road infrastructure, maritime port ownership, digital networks, and alternative financial systems extend China’s virtual reach, while global efforts to shape positive narratives provide a defensive mechanism. Through ever evolving activities, centralized CCP leadership ensures bureaucratic synchronization.
Russia Vignette
Russia provides a distinct and instructive variant of integrated irregular warfare that maps cleanly onto offense, defense, virtual reach, and leadership. Moscow couples targeted information operations, energy coercion, economic pressure, and covert paramilitary action to shape neighbors’ political choices (e.g., Crimea/Donbas) and to fracture allied responses. Domestic media controls, security-service dominance, and legal instruments harden regime resilience against external influence and internal dissent. Cyber operations, strategic use of private military companies and proxy networks, and control over critical information vectors extend Russian influence beyond its borders without large-scale conventional deployments. Centralized decision making and blurred civil–military lines permit rapid, synchronized action across instruments of power, enabling persistent, ambiguous campaigns that complicate attribution and deterrence. Together these elements show how Russia’s IW toolbox achieves strategic effects by deforming political will and institutional cohesion rather than by seizing territory through conventional force.
Implications for Democracies
For democracies, competing effectively in irregular warfare requires strengthening all four components. Offensive capabilities must integrate economic statecraft, cyber deterrence, and legal tools. Defensive resilience depends on cognitive security, economic diversification, cyber protection, and institutional legitimacy in the face of adversaries attacking through unrestricted warfare methods. Virtual reach must be expanded through trusted networks and alliances, while knowledgeable, capable leadership must articulate strategy and sustain public trust.
Conclusion
Irregular warfare defines contemporary great-power rivalry. The framework of offense, defense, virtual reach, and leadership provides a coherent lens for understanding competition that unfolds across systems and domains rather than battlefields. Success depends not on decisive military victory but on resilience, influence, and sustained strategic leadership. Publication of DoDI 3000.07 and creation of the Irregular Warfare Center are great steps. It will take strong, knowledgeable leadership to follow through, synchronizing unique capabilities across the DIMEFIL elements of national power in novel ways to catchup and compete with America’s adversaries.