The US wants Greenland for Arctic and NATO defense, but the coercion it's using undermines the alliance it claims to strengthen. Denmark was a founding NATO member in 1949. Greenland already hosts Pituffik Space Base, America's northernmost military installation. If the US used force against Danish territory, it would theoretically trigger Article 5 collective defense - against the US itself. Even short of force, Denmark could invoke Article 4 consultations when it perceives a threat to its territorial integrity. The strategic contradiction is stark: pressuring an ally to strengthen the alliance weakens the alliance.
Article 5 is NATO's core promise: an attack on one member is an attack on all. It's the foundation of the alliance's deterrent power.
The key text states that members "agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all." This triggers the collective defense obligation.
Geographic scope: Article 6 specifically includes "islands under the jurisdiction of any of the Parties in the North Atlantic area north of the Tropic of Cancer." Greenland is unambiguously covered.
Historical invocation: Article 5 has been invoked exactly once - after September 11, 2001. Denmark, as an ally, sent forces to Afghanistan in response.
The absurdity: If the US used force against Greenland, Article 5 would theoretically trigger collective defense against... the United States. The alliance architecture simply doesn't contemplate one member attacking another.
Denmark's NATO Status
Denmark was one of the twelve original signatories of the North Atlantic Treaty on April 4, 1949. Along with the United States, Canada, and nine other Western democracies, Denmark helped establish the most successful military alliance in history.
As a founding member, Denmark has participated in NATO's collective defense architecture from the beginning - including hosting early warning systems and contributing to alliance operations from Korea to Afghanistan.
Greenland's Strategic Importance to NATO
Greenland occupies some of the most strategically critical real estate on Earth for North Atlantic defense:
- GIUK Gap: Greenland forms the western anchor of the Greenland-Iceland-UK gap, the critical chokepoint for Russian naval forces attempting to enter the Atlantic
- Arctic Access: As Arctic ice recedes, Greenland's position becomes more critical for monitoring new shipping routes and potential military transit lanes
- Missile Defense: Early warning radar systems in Greenland are essential components of North American aerospace defense
- North Atlantic Surveillance: Monitoring Russian submarine activity in the North Atlantic requires Greenland-based infrastructure
The United States has maintained a military presence in Greenland since 1941. Pituffik Space Base (renamed from Thule Air Base in 2023) is America's northernmost military installation, located 750 miles north of the Arctic Circle.
- Hosts ballistic missile early warning radar systems
- Supports satellite tracking and space surveillance operations
- Provides logistics for Arctic operations
- Operates under the 1951 Defense of Greenland Agreement between Denmark and the US
The US already has what it needs for defense purposes through existing agreements. The push for acquisition goes beyond military necessity.
Article 5: Collective Defense
Collective Defense Obligation
The Heart of the NATO Alliance
Geographic Scope
Article 6 of the NATO Treaty specifies that Article 5 applies to attacks on the territory of any Party "in Europe or North America" and specifically includes "the Algerian Departments of France" (now obsolete) and "the territory of Turkey."
Critically for this analysis, Article 6 also covers attacks on "the islands under the jurisdiction of any of the Parties in the North Atlantic area north of the Tropic of Cancer." Greenland unambiguously falls within this definition.
The Absurdity: Article 5 Against the US
If the United States used armed force against Greenland - Danish territory protected under Article 5 - it would theoretically trigger the collective defense obligation against the attacker: the United States itself.
This is not a realistic scenario in practice, but it illustrates the structural incoherence of a NATO member threatening another member's territory. The alliance architecture simply does not contemplate one member attacking another.
Article 5 has been invoked exactly once in NATO's history - after the September 11, 2001 attacks on the United States. Denmark, as an ally, sent forces to Afghanistan in response.
The same alliance framework that brought Denmark to America's defense would, theoretically, bring NATO members to Denmark's defense against any armed attack on Greenland - including from the United States.
This isn't about legal technicalities. It's about what alliances mean. An alliance where members threaten each other's territory is not an alliance at all.
Hypothetical: Could an independent Greenland join NATO on its own, solving the "acquisition" problem while securing US strategic interests?
The pathway: Greenland could theoretically (1) become independent through the existing Danish self-determination framework, then (2) apply for NATO membership as a sovereign state.
Article 10 requirements: NATO membership requires unanimous consent of all existing members. An independent Greenland would need approval from all 32 current NATO states.
Why this doesn't solve the US objective:
- Greenland would be a sovereign NATO ally, not US territory
- The US would still need Greenlandic consent for any expanded military presence
- Greenland could make its own foreign policy choices as a member
- This provides alliance coverage but not territorial control
The real question: If the goal is Arctic defense, an independent Greenland in NATO achieves that. If the goal is territorial control, this pathway doesn't deliver it - revealing that security isn't the only motivation.
Article 4: Consultation Mechanism
Consultation When Threatened
The Early Warning System
What Article 4 Does
Article 4 is the alliance's consultation mechanism - a way for any member to raise concerns about threats before they escalate to the level requiring Article 5. It triggers North Atlantic Council discussions and collective consideration of the threat.
Could Denmark Invoke Article 4 Against US Pressure?
This would be unprecedented, but the treaty text supports it. Article 4 can be invoked when a party believes its "territorial integrity" or "political independence" is threatened. US pressure on Denmark to cede Greenland - especially combined with threats of economic coercion or statements refusing to rule out military options - could plausibly be characterized as threatening Danish territorial integrity.
An Article 4 invocation would:
- Force formal NATO Council consultations on the issue
- Put other allies on record regarding the pressure campaign
- Internationalize what the US wants to frame as a bilateral issue
- Create significant diplomatic and political costs for the US
Historical Article 4 Invocations
| Year | Invoking State | Threat Context |
|---|---|---|
| 2003 | Turkey | Threat from Iraq during lead-up to US invasion |
| 2012 | Turkey | Syrian civil war spillover, border incidents |
| 2014 | Poland, Lithuania, Latvia, Estonia | Russian annexation of Crimea |
| 2015 | Turkey | ISIL attacks and border security |
| 2022 | Poland, Lithuania, Latvia, Estonia, Czech Republic, Slovakia, Bulgaria, Romania | Russian invasion of Ukraine |
Every historical Article 4 invocation has been against external threats - from Iraq, Syria, ISIL, or Russia. A Danish invocation against US pressure would be the first time the mechanism was used to address a threat from within the alliance.
Key Alliance Implications
Click each card to explore the specific implications for NATO:
The Strategic Contradiction
- The stated goal: Acquire Greenland to strengthen Arctic and NATO defense
- The method: Pressure, economic coercion, refusal to rule out force against a NATO ally
- The result: Weakened alliance trust, damaged credibility, precedent for intra-alliance coercion
- The irony: The US is undermining the alliance it claims to be strengthening
The United States already has what it needs in Greenland for defense purposes. Pituffik Space Base operates under existing agreements. Defense cooperation can be expanded through negotiation. The push for acquisition - and the coercive methods being used - go far beyond military necessity.
If the goal is genuinely Arctic defense and NATO strengthening, the methods being employed are counterproductive. If the goal is something else - prestige, resources, political positioning - then the NATO defense rationale is a pretext.
European Ally Reactions
German officials have expressed concern about the precedent of pressuring NATO allies. Germany's position emphasizes that territorial disputes within the alliance should be resolved through diplomacy, not coercion.
France has historically championed European strategic autonomy. US pressure on Denmark reinforces French arguments that Europe cannot rely solely on American security guarantees and must develop independent capabilities.
Poland, which depends heavily on US security commitments against Russia, faces a dilemma. Supporting Denmark risks US displeasure; silence risks endorsing a precedent that could affect Polish interests.
Norway, with its own Arctic territories and close relationship with both the US and Denmark, has expressed solidarity with Denmark while seeking to avoid public confrontation with Washington.
The UK, balancing its "special relationship" with the US against European solidarity and its own overseas territories, has been notably cautious in public statements while privately expressing concern.
EU officials have reminded Washington that Greenland, while outside the EU, remains associated with it through Denmark's membership. Pressure on Denmark is pressure on an EU member state.
- Denmark is a founding NATO member with defense commitments dating to 1949
- Greenland is covered by Article 5 as Danish territory in the North Atlantic
- Article 4 consultation could be invoked against US pressure - unprecedented but textually supported
- Alliance coherence is damaged when members pressure each other over territory
- The stated goal contradicts the method - you can't strengthen NATO by coercing NATO allies
- European allies are watching and drawing conclusions about US reliability
Return to the Greenland Acquisition pillar page with interactive tools.
Why "military option on the table" rhetoric triggers UN Charter Article 2(4).
Every actor who gets a veto: Denmark, Greenland voters, US Senate, more.
How each pathway works: basing, cession, independence-first. What breaks each one.
67 Senate votes, House appropriations, implementing legislation. The domestic hurdles.
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