Journal entry, 19 January 2026 (London)
The Greenland dispute has pushed NATO into a category of crisis it was never built to manage: coercion (and implied escalation risk) by the alliance’s principal power against a fellow member. That is why the most consequential question tonight is not “Who owns Greenland?” but “What happens to a mutual-defence alliance when the coercive actor is inside the pact?”
1) Article 5 is the cornerstone — but it presumes an external attacker
NATO’s founding logic rests on Article 5: an armed attack against one Ally “shall be considered an attack against them all”, with each member taking “such action as it deems necessary” to restore security. (NATO, 1949; NATO, 2025). (NATO)
That text is powerful precisely because it codifies solidarity against an external aggressor. It is less clear—politically and practically—when the perceived threat originates from within the alliance. The House of Commons Library briefing captures the systemic fear plainly: if the United States were to use force against Denmark to secure Greenland, the mutual-defence foundation on which NATO rests would be jeopardised. (House of Commons Library, 2026). (House of Commons Library)
This is the alliance’s constitutional paradox: NATO is designed to deter aggression, but it has no comfortable script for intra-alliance coercion that touches territorial integrity.
2) “If the US attacks a NATO country, everything would stop”
One reason the dispute escalated so rapidly is that senior European voices framed it as existential. The Commons Library briefing records Denmark’s Prime Minister Mette Frederiksen warning that if the US were to militarily attack another NATO country, “everything would stop”—including NATO and the post-war security order—and notes EU Commissioner Andrius Kubilius agreeing that such an outcome would mean the “end of NATO”. (House of Commons Library, 2026). (House of Commons Library)
The Guardian’s own analysis makes the same underlying point: Article 5 does not envisage a scenario where a NATO member becomes the aggressor against another member, and there is no easy internal mechanism for resolving that without paralysing the alliance. (The Guardian, 2026). (The Guardian)
The message is consistent across these accounts: the issue is not simply Greenland; it is NATO’s credibility as a rules-based collective defence institution.
3) NATO leadership’s holding line: keep the alliance intact, widen the Arctic frame
Against that backdrop, NATO’s Secretary General has taken an explicitly stabilising approach. The Commons Library briefing notes Mark Rutte’s statement on 13 January 2026 that “the US is absolutely committed to NATO”, while emphasising that greater European defence spending and collective action on Arctic security would help shore up the alliance. (House of Commons Library, 2026). (House of Commons Library)
Rutte’s remarks at the Renew Europe Global Europe Forum underline the intended reframing: not “Greenland as a bilateral contest”, but “the High North as an alliance-wide security theatre” (Greenland, yes, but also Iceland, Norway, Sweden, Finland, Canada and the US). (NATO, 2026). (NATO)
This is classic alliance crisis management: broaden the issue into shared interests, keep doors open, and reduce incentives for member states to choose between solidarity and survival.
4) European signalling inside NATO: sovereignty language plus “shared transatlantic interest”
The eight-country statement (Denmark, Finland, France, Germany, the Netherlands, Norway, Sweden and the UK) is best read as a NATO-facing document as much as a US-facing one. It asserts “full solidarity” with Denmark and Greenland and warns tariff threats risk a “dangerous downward spiral”, while describing Arctic security as a “shared transatlantic interest”. (Government of Sweden, 2026). (Regeringskansliet)
This is a deliberate balancing act: Europe refuses to normalise coercion, but also avoids language that would make alliance repair impossible.
5) The strategic reality underneath the legal dilemma
Even where legal principles are clear, power asymmetry complicates response options. NATO’s deterrence posture relies heavily on US capabilities, command structures, and enabling assets. The Commons Library briefing highlights the scale imbalance by pointing to the US share of NATO defence spending and the extent of US forces and command integration in Europe—facts that make “punishing” the United States institutionally far harder than criticising it politically. (House of Commons Library, 2026). (House of Commons Library)
This is why the dispute is uniquely destabilising: it pits norms (sovereignty and non-coercion) against dependence (capability reliance) inside the same organisation.
What this episode establishes
NATO’s Greenland dilemma is not, primarily, about whether allies can disagree—they often do. It is about whether the alliance can survive an episode where:
- the coercive instrument is deployed against allies, and
- the implied end-state touches territorial integrity, and
- the coercer is the alliance’s central military and political backbone. (House of Commons Library, 2026; The Guardian, 2026). (House of Commons Library)
The alliance can manage disputes; it struggles to manage precedents. Tonight, Greenland looks like a precedent battle.
References
Government of Sweden (2026) ‘Statement by Denmark, Finland, France, Germany, the Netherlands, Norway, Sweden and the United Kingdom’, 18 January. (Regeringskansliet)
House of Commons Library (2026) President Trump and Greenland: Frequently asked questions, Research Briefing, 21 January. (House of Commons Library)
NATO (1949) The North Atlantic Treaty, 4 April (official text). (NATO)
NATO (2025) ‘Collective defence and Article 5’, updated 12 November. (NATO)
NATO (2026) ‘Keynote address by NATO Secretary General Mark Rutte at the Renew Europe Global Europe Forum 2026 (transcript)’, 13 January. (NATO)
The Guardian (2026) ‘How a US takeover of Greenland would undermine Nato from within’, 6 January. (The Guardian)