Greenland: “If the United States chooses to militarily attack another NATO country, then everything stops,” warns Danish prime minister

From Copenhagen to Nuuk, leaders in Denmark and Greenland are drawing a clear line in the snow as Donald Trump again talks of “taking” Greenland - rhetoric that cuts across the basic assumptions underpinning NATO and Europe’s security.

What makes Greenland so strategically attractive?

With roughly 57,000 residents, Greenland sits at the centre of today’s Arctic power contest. The island holds significant mineral resources, much of them still undeveloped, and its location on crucial routes effectively makes it a vast, frozen aircraft carrier in the North Atlantic.

• The US already runs a major base at Thule in northern Greenland.
• In the Cold War era, Washington operated about a dozen facilities across the island.
• Climate change is making more Arctic waters accessible to commercial shipping and military patrols.
• China and Russia have broadened their activity across the wider Arctic.

In December, Trump said Russian and Chinese ships were “everywhere” off Greenland’s coastline. China has shown interest in mining and infrastructure schemes, while Russia continues upgrading its Arctic fleet and military presence.

Denmark has sought to answer those pressures. In 2025, Copenhagen set aside about 90 billion Danish kroner for Arctic security, including spending on radars, patrol ships and surveillance capabilities. Frederiksen rejects Trump’s assertion that the area is left undefended, yet Washington’s story of an Arctic security “gap” feeds calls for a bigger US role - and, in Trump’s framing, more direct control.

How Danish, US and NATO interests collide over Greenland

At the heart of the dispute are three intersecting realities:

Actor	Position
Denmark	Retains sovereignty over Greenland, oversees foreign and security policy, and depends heavily on NATO guarantees.
Greenland	Operates under self-rule, manages domestic affairs, and increasingly insists on its right to determine its longer-term status.
United States	Treats Greenland as a key Arctic outpost, hosting vital military capabilities and monitoring rival powers.

NATO’s underlying bargain assumes members can count on the US under Article 5 - not face suggestions that Washington might slice away allied territory. Frederiksen’s alarm about “everything stopping” reflects the concern that, if the use of force against an ally is even contemplated, the alliance’s core promise begins to look conditional.

Denmark warns of a breaking point inside NATO

Danish Prime Minister Mette Frederiksen delivered her most severe warning so far to Washington, arguing that the post-war security system would unravel if the United States ever pointed weapons at a fellow NATO ally.

“If the United States chooses to militarily attack another NATO country, then everything stops. Including our NATO, and the security built since World War II,” she warned on Danish television.

She spoke after fresh Trump comments about annexing Greenland - the huge Arctic territory within the Kingdom of Denmark that nonetheless enjoys extensive autonomy. Trump described Greenland as a national security asset the US “needs”, implying Denmark would be unable to defend it adequately.

Frederiksen said she is “doing everything” she can to avoid the scenario she outlined, a rare moment when a close US partner publicly raises the possibility that Washington could be perceived as a risk - not just a guarantor - within the Atlantic alliance.

Greenland pushes back: “enough now”

In Nuuk, Greenland’s Prime Minister Jens‑Frederik Nielsen responded to Trump’s newest remarks - including talk of “taking care of” the island within weeks - with unusually blunt language.

“Enough now,” he said, calling on Washington to stop treating Greenland as something to be seized or as a square on a geopolitical chessboard.

Nielsen argued that Greenland should not be likened to Venezuela, where a recent US special forces operation prompted debate about precedent. Trump had suggested allies should take their own lessons from that mission.

“Our country is not comparable to Venezuela. We are a democratic country and have been for many, many years,” Nielsen stressed, emphasising to US audiences that Greenland’s political status is backed by clear legal safeguards.

Speaking at a press conference in Nuuk, he also urged Greenlanders to stay calm: the US cannot simply “conquer” the island, he said, and the aim is to rebuild the “good cooperation” that once existed with Washington. Even so, his government intends to be more forthright, irritated that key matters are being handled “through the media and by various detours” rather than directly.

Why Trump’s team says the US “should have” Greenland

Among Trump’s allies, the tone is markedly different. Stephen Miller, a close adviser, repeated that “the United States should have Greenland” and brushed aside questions about a potential US military move.

He argued there was “no need to think or even talk” about military conflict, claiming nobody would fight the US over Greenland’s future.

This messaging followed a post by Miller’s wife, who shared an image on X showing Greenland coloured like the US flag alongside the caption “soon”. Politicians in Nuuk and Copenhagen were enraged, viewing it as a deliberate provocation rather than a throwaway meme.

Frederiksen replied on Sunday evening with a pointed message directed squarely at Washington: “I urge the United States to end its threats against a historic ally.” She described the idea that the US could simply take Greenland as “completely absurd”.

The phrasing is significant. Denmark seldom addresses the United States in such terms - particularly as it sources much of its military hardware from American suppliers and has typically aligned itself closely with US foreign policy.

Europe rallies around Denmark and Greenland

Across Europe, responses came fast. France’s foreign ministry spokesman Pascal Confavreux said borders cannot be altered by force and promised solidarity with Denmark. Sweden, Norway and Finland echoed that stance, stressing that only Greenland and Denmark can decide Greenland’s future.

Finnish president Alexander Stubb wrote that “nobody decides for Greenland and Denmark except Greenland and Denmark themselves”.

The European Union also intervened via its foreign affairs spokesperson Anitta Hipper, saying the EU will continue defending national sovereignty, territorial integrity and the inviolability of borders - particularly when the territory of a member state is being challenged.

In London, Prime Minister Keir Starmer backed Frederiksen’s position, saying she “is right regarding the future of Greenland” and stressing that decisions on the island rest solely with “Greenland and the Kingdom of Denmark”. For a UK government seeking closer European relations while maintaining the transatlantic link, it was a measured but unmistakable signal.

Greenlandic public opinion resists US attachment

Behind the official diplomacy, Greenlandic public sentiment has already been recorded. A poll released in early 2025 found 85% of Greenlanders opposed joining the United States, while only 6% supported the idea. Everyone else was undecided or declined to respond.

That polling came after earlier friction, including Trump’s choice to appoint a special envoy for Greenland and a prominent visit by Vice-President J. D. Vance. Those steps amplified concerns that Washington views Greenland less as a partner and more as an asset to be acquired - echoing Trump’s earlier, widely ridiculed suggestion of “buying” the island.

For many in Greenland, the argument also connects to a long-standing debate about self-determination. Some political groupings favour full independence from Denmark at some point this century, funded in part through resource income. Few, however, want to swap Copenhagen for Washington as the ultimate authority.

What this crisis says about NATO’s future

The back-and-forth between Trump, Frederiksen and Nielsen points to a bigger question: how resilient is NATO when a leading member publicly muses about taking territory from another?

NATO’s strength relies on a straightforward exchange: smaller countries accept US leadership, and Washington guarantees their defence. If that leadership begins to appear transactional or coercive, confidence drains away. Frederiksen’s warning that “everything stops” gestures towards a future in which allies start hedging - putting more weight behind European defence structures or exploring other security arrangements.

For Russia and China, visible strain between Washington and Copenhagen over Greenland sends a message of its own. It implies the West still lacks a unified Arctic approach, and that some of the most consequential disputes in the region are unfolding inside alliances rather than solely between adversaries.

Key risks if the standoff escalates

• Greenlandic and Danish politics could harden, making day-to-day defence cooperation with the US far harder to handle.
• Public backing for US bases could weaken, complicating missile warning and satellite tracking activity at Thule.
• Russia and China could find more scope to expand their footprint, arguing Western planning is erratic and self-contradictory.
• NATO unity could fray if other allies fear their own territories might eventually be treated as bargaining chips.

Strategists in European capitals already use Greenland in war-gaming sessions as a test case: what happens when an ally’s internal politics collide with alliance planning in a distant but critical region? These simulations tend to arrive at the same finding: absent careful diplomacy and respect for local communities, military access becomes fragile even when treaties remain intact.

For Greenlanders, the dispute brings both risk and leverage. It heightens the danger of becoming a frontline in great-power rivalry, while also increasing Greenland’s bargaining power over future mining, infrastructure and defence deals. How Nuuk uses that leverage over the next few years may shape not only its ties with Copenhagen and Washington, but the balance of power across the Arctic as sea ice continues to retreat and new shipping routes appear.