Wargame Analysis: NATO Crisis Over U.S. Attempt to Seize Greenland (2026)

Date: January 18, 2026

Executive Summary

This wargame paper evaluates the geopolitical, military, and legal ramifications of a hypothetical U.S. presidential order to seize Greenland by force in 2026. Greenland, although geographically distant, occupies a strategically vital position in the Arctic. It is a self-governing territory within the Kingdom of Denmark and under the umbrella of NATO’s collective defense due to Denmark’s membership.

The paper addresses three primary scenarios:

1. A unilateral U.S. military action without prior NATO presence.
2. U.S. action following preemptive NATO deployment in Greenland.
3. Possible Russian involvement supporting American strategic objectives.

These scenarios illuminate emerging fractures in the post–Cold War alliance structure and test the legal and operational resilience of NATO. The analysis incorporates plausible military operations, strategic calculations, legal interpretations, and alliance politics. The findings underscore NATO’s vulnerability to internal aggression and the emerging complexities of Arctic geopolitics.

Scenario 1: Unilateral U.S. Military Action Against Greenland

In this scenario, the United States acts unilaterally without prior NATO presence on Greenland. The U.S. President, citing national security threats, Arctic resource access, and geostrategic competition with China and Russia, orders U.S. forces to take control of Greenland. This action bypasses Denmark’s sovereignty and the established NATO decision-making process.

Denmark lodges formal protests and convenes the North Atlantic Council (NAC). European NATO members quickly assess the implications for collective defense. The NAC faces an unprecedented challenge: the aggressor is a founding NATO member. Diplomatic channels are overwhelmed, and military planners in Brussels begin urgent consultations.

Potential responses include:

• Coordinated defensive deployment under Danish command.
• Invocation of Article 4 (consultation) but not Article 5 (collective defense).
• Unilateral actions by European states to oppose U.S. occupation.

The outcome hinges on political will and cohesion within NATO. A fragmented response would undermine alliance credibility; a strong unified stance might deter U.S. aggression or lead to internal alliance rupture. The scenario sets the stage for broader intra-NATO confrontations over norms, legality, and leadership.

Scenario 2: NATO Troops Already Deployed in Greenland

Anticipating potential U.S. coercion, Denmark initiates Operation Arctic Endurance with support from key NATO allies. Troops from the United Kingdom, France, Germany, Norway, and Canada are pre-positioned across Greenlandic territory. Their presence symbolizes alliance solidarity and positions NATO forces to deter unilateral action.

Despite warnings, the U.S. President orders an amphibious landing in western Greenland. European troops, embedded with Greenlandic defense units, issue radio warnings and prepare for confrontation. As U.S. naval and air units approach, the situation escalates. Military deconfliction fails, and skirmishes erupt at key access points such as Kangerlussuaq and Thule. This intra-alliance combat marks an unprecedented development.

Politically, NATO enters a state of emergency. The NAC debates Article 5 invocation against one of its own members—a situation for which no legal precedent exists. European leaders call for the suspension of U.S. participation in NATO activities. The U.S. administration, facing Congressional opposition, accuses European allies of betrayal and threatens broader disengagement.

This scenario tests NATO’s institutional integrity and reveals critical flaws in its governance mechanisms under conditions of internal aggression.

Scenario 3: Russian Involvement Supporting U.S. Objectives

This scenario introduces an additional layer of complexity: covert or indirect Russian support for the United States. While no formal alliance is formed, Russia seizes the opportunity to weaken NATO’s cohesion.

The Kremlin launches disinformation campaigns portraying the crisis as European overreach. Simultaneously, Russian cyber units target European military communications in Greenland and NATO headquarters. In the maritime domain, Russian submarines and surface vessels begin Arctic maneuvers near Greenland and the GIUK Gap, signaling strategic alignment without explicit coordination.

This activity compels NATO to divide its attention between deterring U.S. aggression and monitoring Russian advances. Meanwhile, Moscow offers backchannel support to Washington—suggesting coordination on sanctions, Middle East posture, and Arctic economic zones.

The NATO alliance struggles to maintain coherence. Internal divisions deepen as member states disagree on the proper response to dual provocations. This scenario underscores the multidimensional threats posed by strategic opportunism and the vulnerabilities of alliance-based security architectures.

Combined Strategic Assessment

All three scenarios reveal core structural weaknesses in NATO’s design. Built for collective defense against external threats, NATO lacks the internal legal and procedural frameworks to manage intra-alliance conflict. The presence of European forces in Greenland represents a partial deterrent, but also escalates the risk of direct combat. Russia’s involvement exacerbates the crisis by introducing hybrid threats and diverting European resources.

Key strategic takeaways:

• NATO lacks mechanisms to address member-on-member aggression.
• European military cohesion is robust, but political unity remains fragile.
• Russian opportunism is highly effective in exacerbating transatlantic disunity.

This assessment suggests an urgent need for NATO reform, especially regarding Article 5 applicability, Arctic doctrine, and intra-member conflict protocols.

Legal and Political Implications

From a legal standpoint, any unilateral U.S. action against Greenland violates the UN Charter and the North Atlantic Treaty. Denmark, as Greenland’s sovereign authority, is entitled to territorial integrity and protection from aggression—even by an ally.

Within the U.S., such military action would likely exceed the limits of executive authority and violate Congressional war powers. If the President bypassed authorization, legal and constitutional challenges would arise.

Politically, the crisis would damage transatlantic relations irreparably. NATO’s institutional credibility would be severely undermined. European states would likely explore alternative defense structures, while Greenland and the Arctic region would be militarized at a scale not seen since the Cold War.

Conclusion

The hypothetical crisis over Greenland reveals deep structural and doctrinal vulnerabilities within NATO. A unilateral U.S. attempt to seize Greenland—particularly against allied troops—would provoke military confrontation and potentially unravel the alliance. The added variable of Russian hybrid involvement raises the stakes further, drawing Europe into a multifront geopolitical contest.

The crisis scenario demands serious consideration of NATO’s future configuration. Without reforms to address intra-member aggression, hybrid warfare, and Arctic-specific threats, the alliance risks fragmentation in the face of 21st-century strategic realities.

Addendum: Strategic Benefits to the Russian Federation from the Greenland Crisis

Scenario 1: Unilateral U.S. Military Action Against Greenland

Putin’s Strategic Gains:

• Erosion of NATO Unity: A U.S. act of aggression against a NATO-aligned territory forces European allies to question the credibility of NATO’s core deterrent (Article 5), weakening the alliance from within.
• Legitimization of Russian Behavior: The U.S. use of force against a sovereign territory gives Moscow rhetorical ammunition to justify its own interventions in Ukraine, Georgia, and the Arctic.
• Diplomatic Leverage: Russia can position itself as a “rational actor” or even a mediator amid NATO chaos, gaining soft power and undermining Western moral high ground.
• Opportunity for Arctic Militarization: As NATO’s focus turns inward, Russia can accelerate its military and economic expansion across the Russian Arctic with reduced scrutiny or pushback.

Scenario 2: NATO Troops Already Deployed in Greenland

Putin’s Strategic Gains:

• Alliance Entrapment: A direct clash between U.S. and European NATO troops fulfills a long-term Russian goal: sowing conflict among Western states without direct intervention.
• Diversion of NATO Resources: European states and Canada would be forced to reallocate forces and funding toward Arctic defense and intra-alliance security, detracting from collective focus on Eastern Europe and Ukraine.
• Geopolitical Realignment: If NATO fractures or suspends U.S. participation, Russia can exploit the resultant vacuum to cultivate bilateral deals with disaffected NATO or EU states.
• Narrative Control: Kremlin propaganda would frame the crisis as proof that NATO is an unstable relic of the Cold War, justifying Russian-led alternative security frameworks (e.g., CSTO, BRICS security council).

Scenario 3: Russian Involvement Supporting U.S. Objectives

Putin’s Strategic Gains:

• Asymmetric Leverage: By covertly aiding the U.S. or simply exploiting the chaos, Russia gains maximum geopolitical return with minimal direct risk or cost.
• Operational Distraction: Cyber attacks and Arctic naval deployments tie down NATO resources and create vulnerabilities on NATO’s eastern flank.
• Testing Alliance Limits: Russia can observe NATO’s crisis response mechanisms in real-time, identifying gaps in cohesion, interoperability, and command-and-control.
• Strategic Normalization of Hybrid Tactics: As NATO struggles to define responses to internal aggression and hybrid threats, Russia can further normalize cyberwarfare, information ops, and economic coercion as legitimate statecraft tools.

Combined Strategic Assessment

Across all scenarios, the Greenland crisis offers Russia a unique geopolitical windfall:

• Internal NATO polarization benefits Moscow’s long-term goal of a fragmented and ineffective alliance.
• The Arctic, long seen as Russia’s strategic frontier, becomes less contested as NATO faces internal disruption.
• Russia can shift global narratives about the “rules-based order,” equating Western hypocrisy with its own authoritarian assertiveness.

Net Effect for Russia:

Without firing a shot, the Kremlin reaps strategic, psychological, and diplomatic gains from an alliance crisis it neither started nor controls, but can deeply exploit.