Why US wants to take over Greenland when it already holds sweeping military rights over the island

US Secretary of State Marco Rubio told American lawmakers on Wednesday that President Donald Trump intends to pursue the purchase of Greenland, rather than using military force, amidst rising tensions within NATO. Rubio mentioned plans to meet Danish officials next week to discuss the situation. “I’ll be meeting with them next week,” he said. “We’ll have those conversations with them then.” 

White House spokesperson Karoline Leavitt also confirmed that the acquisition of Greenland is being actively discussed by Trump and his national security team. Despite this, both Denmark and Greenland have firmly reiterated that the island is not for sale. Leavitt emphasised that while all options remain on the table, diplomacy is Trump’s primary approach.

Trump is keen to acquire Greenland because of its strategic location between the Arctic and North Atlantic Oceans. He seeks control of the island to "deter our adversaries in the Arctic region", specifically citing the presence of Russian and Chinese vessels. Greenland is a linchpin in the US ballistic missile defence architecture. The US continues to operate the Pittufik Space Base (formerly Thule), which provides essential early warning capabilities for missiles traversing the North Pole. Ensuring total control over this territory would guarantee the security of these assets against potential espionage or sabotage. Meanwhile, climate change is making Greenland’s vast deposits of critical minerals more accessible, and Trump is keen to secure those to reduce reliance on China, which dominates the global supply chain. 

Even as the debate over Greenland intensifies, it is important to note that the US already enjoys significant military rights over the island. The 1951 Greenland Defence Agreement grants Washington extensive operational freedom, effectively giving it near-total control over Greenland’s strategic assets. Under the agreement, the US already wields sweeping military powers that render Greenland an American military fortress in all but name.

What led to the 1951 agreement? 

The 1951 agreement was triggered partly by the Nazi occupation of Denmark during World War II. The Danish ambassador in Washington, who was spared of the perils of the occupation, decided to negotiate a defence agreement for Greenland with the US, since geographically, the island was part of North America. The US was worried that the Nazis could use Greenland as a staging ground to reach the American mainland, as they had already established small meteorological bases on the island’s east coast to relay vital information for its troops in Europe. American soldiers eventually ousted the Nazis and took control of Greenland before the end of the war. 

The 1951 agreement provides a "free hand" for US operations. Washington is authorised to establish and operate "defence areas" as necessary for NATO. Within these areas, the US can construct facilities, station troops, and deepen harbours without paying compensation to Denmark. Crucially, the US commanders have the authority to control the movement of all ships, aircraft, and vehicles within these zones.

Beyond specific bases, the US enjoys the "right of free access to and movement between the defence areas through Greenland" by land, sea, and air. The US aircraft are permitted to fly over and land on any territory in Greenland, including its territorial waters, without restriction. Furthermore, the US retains "exclusive jurisdiction" over its defence areas and over any offences committed by its personnel on the island. If the US wishes to expand, the treaty allows it to conduct topographic and hydrographic surveys to select new defence areas. Analysts note that if the US simply requested to build a new airfield or port under this existing framework, Denmark would almost certainly agree.

Notwithstanding such extensive rights, the Trump administration seeks full ownership. Trump has repeatedly expressed his desire to acquire the island, a pursuit dating back to his first term. While Denmark and Greenland have clearly rebuffed him, Washington appears unwilling to concede. Aside from issuing veiled threats, the Trump administration is also attempting to woo the Greenlandic population directly. Offers of investment in education and economic development are aimed at encouraging independence from Denmark, after which Washington would be able to strike a deal directly with Nuuk.

Another possible mechanism for the US to gain control is a "Compact of Free Association," similar to the agreements Washington has with Palau and the Marshall Islands. This would involve Greenland declaring independence, after which the US would provide defence and economic assistance in exchange for unrestricted military access.

The White House has stated that utilising the US military is "always an option". Although considered unlikely by some due to the catastrophic risk to the NATO alliance, the US special forces could theoretically seize strategic points in Nuuk quickly, given Greenland’s lack of a standing army. However, Danish officials have warned that such an attack would end the NATO alliance and have ramped up their own military presence to deter such moves.