Small Wars in the New Strategic Era: Why the United States Must Prepare for a World of Limited Conflict

Abstract

The 2025 National Security Strategy (NSS) signals a deliberate shift toward restraint, hemispheric prioritization, and selective engagement. Yet history shows that when major powers seek to avoid large wars, competitors often exploit gray-zone tactics, proxy campaigns, and limited conflicts to test boundaries. The United States must therefore prepare for an era in which small wars become more frequent, more ambiguous, and more strategically consequential for the balance of power and the credibility of American leadership.

Introduction

The United States is entering a strategic realignment unlike any since the end of the Cold War. The 2025 National Security Strategy tightens the definition of vital interests, reorients national defense toward a revitalized industrial base and homeland protection, and places greater expectations on allies to shoulder regional burdens. By design, it moves the United States away from open-ended expeditionary campaigns and toward a more disciplined, selective posture abroad. The document explicitly frames this shift as a response to domestic demands for restraint, fiscal pressure, and the recognition that the United States cannot and should not police the international system alone.

Days later, Secretary of War Pete Hegseth reinforced this direction at the Reagan National Defense Forum, announcing the end of “undefined wars” and promising a new era of clarity in objectives, timelines, and exit strategies in the use of force. His remarks signaled to allies and adversaries alike that Washington intends to be more judicious about when and where it fights—and far more skeptical about long-duration stability operations.

This logic is understandable and, in many respects, overdue. But it is also incomplete. Strategic restraint is never interpreted in a vacuum. Adversaries do not simply read official texts; they infer limits, probe thresholds, and search for opportunities. Throughout the Cold War and the post-9/11 era, whenever Washington narrowed its definition of vital interests or telegraphed fatigue, determined competitors responded not by standing down, but by shifting confrontation into the space below open war. Today, that pattern is manifesting again—only this time with faster technology, more porous information environments, and more globalized economic leverage.

The forthcoming National Defense Strategy (NDS) must therefore start from a hard truth: if the United States intends to avoid major war, it must be prepared for a rising tempo of limited, ambiguous conflicts that challenge its interests without ever quite crossing the threshold of large-scale combat.

The Return of Competition Below the Threshold of War

Strategic restraint creates incentives for competitors to seek advantage in what is often called the “gray zone”—the murky space between peace and overt armed conflict. States and non-state actors are increasingly using cyberattacks, disinformation campaigns, economic coercion, covert action, and paramilitary operations to shape the environment without triggering traditional thresholds for war. Recent analysis has described this trend as a “shadow war” in which sabotage, cyber intrusions, and covert violence are stitched together into a long-duration campaign of pressure against Western societies and infrastructure.

Russia, China, Iran, and their partners are not improvising; they are adapting well-understood strategic theory. Classical deterrence holds that nuclear-armed powers will seek relative advantage by competing just below the level of open war. The strategic logic is simple: if major escalation is too risky, then small, deniable, and incremental moves become more attractive. When Washington advertises its reluctance to fight large wars, it invites adversaries to test what they can get away with short of that line.

Regional Expressions of Limited Conflict and Hybrid Pressure

Europe: Sabotage, Cyber Pressure, and “Shadow War”

In Europe, Russia is conducting a sustained campaign of hybrid operations designed to pressure Western governments, erode cohesion, and probe defenses without triggering NATO’s collective defense clause. European security services have uncovered plots targeting logistics hubs, rail lines, and other critical infrastructure, often using proxy operatives recruited and paid online.

These activities are part of a wider “shadow war” that includes sabotaging undersea cables and pipelines in the Baltic region, testing responses to maritime incidents, and probing the resilience of energy and data networks. In response, NATO and the EU have launched specialized coordination cells and maritime missions to monitor vulnerable infrastructure, and several states have begun detaining suspected operatives and imposing targeted sanctions.

The pattern is familiar. During the early Cold War, Soviet services used covert action, political warfare, and subversion to reshape European politics without provoking direct war with the United States. Today’s Russian campaign follows the same logic, but with modern tools and a sharper focus on infrastructure, information, and energy.

Middle East and the Red Sea: Proxies, Missiles, and Maritime Disruption

In the Middle East, Iran and its aligned groups have long relied on proxies, missile arsenals, and cyber tools to apply pressure while maintaining plausible deniability. The war in Yemen and the broader Red Sea crisis have illustrated how relatively low-cost systems—drones, cruise missiles, anti-ship weapons—can disrupt global trade routes without a formal declaration of war. Since late 2023, Houthi attacks on commercial shipping in the Red Sea and Gulf of Aden have forced shipping companies to reroute vessels around the Cape of Good Hope, raised insurance and freight costs, and demonstrated how regional actors can hold global trade at risk.

These actions operate in a space that is neither piracy nor conventional war. They are calibrated to signal solidarity with broader regional causes, impose costs on Western and regional adversaries, and test how far they can push without triggering a decisive response. Even when multinational coalitions form to protect shipping and conduct strikes against launch sites, the attackers often maintain enough deniability and dispersion to continue harassment at a sustainable level.

Indo-Pacific: China’s Gray-Zone Pressure on Maritime Frontiers

In the Indo-Pacific, China is pursuing its own form of gray-zone coercion. Rather than risking an immediate, full-scale confrontation, Beijing combines coast guard operations, maritime militia deployments, air incursions, cyber intrusions, and legal warfare to reshape facts on the ground (and at sea) over time. Studies of China’s maritime behavior document how its forces sustain near-daily presence around disputed reefs and shoals, harass fishing and energy activities of neighbors, and employ ramming, water-cannoning, and blocking maneuvers to intimidate Philippine and other regional vessels without crossing into major combat.

These tactics mirror “salami-slicing” strategies: each individual incident may seem too small to warrant escalation, but the cumulative effect is a profound shift in control and perception. The same logic applies in the cyber domain, where Chinese actors mount persistent campaigns of espionage, data theft, and disruptive activity against regional governments and sectors tied to maritime disputes.

Africa and the Western Hemisphere: Proxies, Mercenaries, and Economic Leverage

Across Africa’s Sahel region, Russia has expanded influence through quasi-private military companies such as Wagner and its successor formations. These groups bolster embattled regimes, gain access to resources, and undertake brutal counterinsurgency operations under the guise of partnership. In practice, they deepen instability, enable coups, and displace Western and regional initiatives without triggering a clear, conventional confrontation with the United States or NATO.

In Latin America and the broader Western Hemisphere, both Russia and China are using information operations, economic deals, infrastructure investments, and security partnerships to gain footholds near the United States. These engagements are often framed as benign development or commercial projects, but they carry clear strategic implications—from access to ports and telecommunications infrastructure to political leverage in multilateral forums.

Why Strategic Restraint Produces More Small Wars

The central paradox of the new strategic era is that a United States determined to avoid major war is likely to face more frequent small ones. History suggests that when a dominant power tightens its definition of vital interests, competitors respond by identifying “edges” where they can act aggressively without crossing the line that would trigger full-scale retaliation.

During the early Cold War, Washington’s determination to avoid direct war with the Soviet Union did not produce a peaceful status quo; instead, it generated a series of limited conflicts—Korea, Vietnam, proxy wars in the Middle East and Africa, and covert struggles in Latin America. Each was calibrated to test how far aggression could go without provoking nuclear escalation. Strategic restraint at the top of the escalation ladder pushed competition downward, into smaller but still deadly confrontations.

Today, the 2025 NSS and accompanying rhetoric of restraint risk creating similar dynamics. Adversaries will likely conclude that Washington will fight only when core treaty obligations or homeland defense are at stake. That perception makes gray-zone campaigns, sabotage, disinformation, proxies, and limited territorial grabs more—not less—attractive. For rivals, the “sweet spot” lies in operations that hurt American interests and allies, but fall just short of the threshold that would make a major war politically inevitable.

Implications for the National Defense Strategy

If the NSS establishes the broad logic of restraint, the NDS must translate that logic into a strategy for managing a world of limited conflict. Four implications stand out.

1. Attribution and Decision Speed as Core Deterrent Functions

Hybrid aggression thrives on ambiguity and delay. Adversaries count on Western leaders needing time to investigate, debate, and build consensus before acting. The United States must therefore treat rapid attribution and decision-making as central deterrent functions, not afterthoughts. Investments in fused intelligence, persistent sensing, and analytic tools should enable policymakers to quickly determine who is responsible for cyberattacks, sabotage, or covert violence and link those findings to pre-agreed response options with allies.

Recent recommendations from European and transatlantic analysts stress that resilience alone is not enough; credible responses must impose costs that outweigh the perceived benefits of hybrid action.

2. Forces Designed for Distributed, Multi-Domain, Short-Notice Operations

The U.S. military must be able to operate effectively in crisis periods that are short, ambiguous, and politically constrained. That means fielding forces that are:

• Smaller and more distributed,
• Able to deploy quickly into contested environments,
• Equipped with unmanned systems, cyber tools, and precision fires, and
• Integrated across land, sea, air, cyber, and space from the tactical to the strategic level.

Ongoing conflicts—from Ukraine’s use of drones and long-range strikes against Russian forces and shipping to coalition naval operations countering threats in the Red Sea—already demonstrate how rapidly evolving technologies and tactics can reshape the character of limited war.

The NDS will need to prioritize experimentation, joint force design, and concepts that prepare U.S. and allied forces to respond to multiple, simultaneous gray-zone and limited conflicts rather than a single, large conventional campaign.

3. Alliances and Partners as a System for Gray-Zone Defense

Alliances remain the United States’ greatest strategic advantage, but they are not yet optimized for gray-zone competition. Many current structures and processes are designed for Article 5-type contingencies or large-scale combat operations, not for sabotage, cyber pressure, information warfare, or maritime harassment.

The NDS should encourage allies to:

• Align red lines and thresholds for response to hybrid attacks,
• Share intelligence and legal tools for pursuing perpetrators across borders,
• Coordinate sanctions, cyber countermeasures, and law-enforcement actions, and
• Develop joint doctrines for countering gray-zone campaigns in key theaters, from the Baltic and Black Seas to the South China Sea and Red Sea.

Progress is emerging, from NATO’s undersea infrastructure coordination efforts to new maritime coalitions in the Red Sea and increased security cooperation with Indo-Pacific partners facing Chinese coercion. But these initiatives remain uneven and often reactive; the NDS should elevate them to core lines of effort.

4. Domestic Political Resilience and Strategic Communication

Finally, limited conflicts are not just contests of firepower; they are contests of narrative, legitimacy, and endurance. Adversaries aim their gray-zone campaigns at domestic vulnerabilities—polarization, disinformation, economic inequality, and fatigue with foreign engagement. A strategy for small wars must therefore include measures to:

• Strengthen public understanding of why limited conflicts matter,
• Protect democratic institutions and elections from foreign interference, and
• Prepare the American people for a long, uneven competition marked by sporadic crises rather than a single decisive clash.

Without this political foundation, even the best-designed military posture may prove insufficient. Strategic patience and societal resilience are as important as ships, aircraft, or cyber tools.

Conclusion

The 2025 National Security Strategy reflects a disciplined and necessary correction in American statecraft. It seeks to restore balance between ends and means, prioritize the homeland and industrial base, and align global commitments with domestic realities. Yet the strategic environment will not sit still in response. Rivals are already positioning themselves to exploit the seams of American restraint, relying on gray-zone campaigns, proxies, and limited conflicts to gain advantage.

The next decade is unlikely to be defined by a single decisive war. Instead, it will almost certainly feature a series of small, fast-moving contests—at sea lanes, in cyber networks, along fragile borders, and within contested information spaces. If the United States wishes to prevent large wars, it must accept the reality of this environment and prepare now to compete, deter, and, when necessary, fight effectively in it.

The task for the NDS is not simply to say “no” to another generation of large-scale interventions. It is to build a strategy, a force, and an alliance system capable of prevailing in the world of limited conflict that strategic restraint inevitably invites.

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