Greenland gambit: How Trump's tariff threat is testing alliances

US President Donald Trump has further escalated his campaign to bring Greenland under American control, threatening to impose tariffs on countries that oppose Washington’s ambitions. Speaking at a White House event on Friday focused on tariffs he has slapped on pharmaceutical imports from the European Union, Trump signalled that economic coercion could be extended for Greenland, too. 

“I may put a tariff on countries if they don’t go along with Greenland, because we need Greenland for national security,” said Trump.

Trump did not specify which countries might be targeted, or under what legal authority such tariffs would be imposed. Instead, he drew a parallel with his earlier threats against the EU’s pharmaceutical exports, framing trade penalties as a legitimate tool of national leverage. It seems like a ploy to unsettle allies and force negotiations.

Trump says control of Greenland is essential to prevent strategic rivals from filling a dangerous vacuum. “If we don’t go in, Russia is going to go in, and China is going to go in,” he said. Trump has also linked Greenland to his administration’s proposed “Golden Dome” missile defence system, arguing that the territory’s geography makes it indispensable for early warning and interception capabilities.

Trump has described any outcome short of American control as “unacceptable”. While he has said that diplomacy would be preferable, he has repeatedly refused to rule out the use of force. Estimates circulating in Washington suggest that purchasing Greenland outright could cost the United States as much as $700 billion, a figure that has done little to temper his rhetoric.

The latest ultimatum comes amid a flurry of diplomatic activity and growing resistance from both Denmark and Greenland, which is a semi-autonomous territory within the Danish kingdom. Earlier this week, Denmark’s foreign minister, Lars Lokke Rasmussen, and Greenland’s foreign affairs minister, Vivian Motzfeldt, met in Washington with Vice President J.D. Vance and Secretary of State Marco Rubio. Rasmussen said the talks yielded no breakthroughs, though the sides agreed to establish a high-level working group. Reports from the meetings indicate that Vance floated the idea of finding a “middle ground”, a phrase that alarmed Danish diplomats wary of any discussion that might legitimise American claims.

In Greenland itself, reactions have been blunt. Prime Minister Jens-Frederik Nielsen declared that if forced to choose between Washington and Copenhagen, Greenland would stand with Denmark, NATO and the European Union. Sara Olsvig, chair of the Inuit Circumpolar Council, said Indigenous Inuit did not wish to be colonised again and that there is “no such thing as a better coloniser”.

European allies have moved quickly to demonstrate solidarity with Denmark. France, Germany and the UK are among several NATO members that have dispatched small military contingents to Greenland as part of a reconnaissance mission ahead of the “Arctic Endurance” exercise. A small French force has already arrived in Nuuk, with President Emmanuel Macron saying it would soon be reinforced with “land, air, and sea assets”. Senior French diplomat Olivier Poivre d’Arvor described the deployment as a political message: “This is a first exercise... we’ll show the US that Nato is present.”

Washington, too, has acknowledged signs of unease. A bipartisan delegation of US lawmakers travelled to Copenhagen to meet Danish and Greenlandic leaders, and “lower the temperature”. Led by Democratic Senator Chris Coons, the group sought to reassure allies that Congress views Greenland as a partner, not a prize. Republican Senator Lisa Murkowski said that the vast majority of Americans do not support acquiring the island, and she and Senator Jeanne Shaheen have introduced legislation to bar the use of defence or state department funds to annex Greenland without the consent of the relevant NATO ally.

Despite the political storm, the United States already maintains a significant strategic footprint on the island. The Pituffik base, a missile-monitoring station on Greenland’s northwestern tip, has been operated by the US since the Second World War. Major-General Soren Andersen, head of Denmark’s Joint Arctic Command, has played down talk of conflict between allies, calling it “hypothetical” and saying his forces are focused on potential Russian activity. He expects Moscow’s Arctic presence to grow in the coming years.

Trump’s envoy to Greenland, Jeff Landry, insists that a deal remains possible. The president, he said, has “laid the markers down” and is offering liberty, economic strength and protection rather than conquest. For now, the White House maintains that failing to secure Greenland would leave a “big hole in national security”. For America’s allies, that claim has become a test not only of Arctic strategy, but of how far US power is willing to push the boundaries of partnership.