The legal implications of Trump’s designs on Greenland

The US government treating a nation, which has largely voiced its opposition to US ownership and leadership, as a real estate transaction is pretty incredible, but recent events in Venezuela prove nothing is impossible. While purchasing territory was not uncommon in the 19^th century, it would be an anomaly in the largely post-colonial present day.

As reported by the Sydney Morning Herald in 2019, The Brookings Institute estimates that Greenland should be valued at half a trillion dollars. With a land mass four times larger, and inclusive of GDP and land value, Australia was valued at around $233 trillion in 2019. The GDP of Greenland was $3 billion in 2019, while Australia’s GDP is about $1.8 trillion (in USD) – close to 470 times as much.

The US President, a real estate dealer at heart, has pitched the idea of buying Greenland in the interests of US national security. There’s precedent, and there’s Venezuela, so the world is justified in taking the notion seriously.

Right of self-determination

Professor Ben Saul is Challis Chair of International Law at the University of Sydney and the United Nations Special Rapporteur on the Promotion and Protection of Human Rights and Fundamental Freedoms while Countering Terrorism. He says, “Under international law, sovereignty can be transferred by the sale of a territory, but it must satisfy the requirements of the right of self-determination under international law. In this case, it would require the dual popular approval of both the people of Greenland and the people of Denmark, for example expressed through referenda. It would also have to meet any domestic constitutional and legal requirements.”

The US originally raised the possibility of purchasing Greenland from Denmark in 1867, but what’s old is new again when it comes to the US President’s policy agenda. Consider the Trump-coined “Donroe Doctrine”, the rationale for the recent occupation of Venezuela, as an example of recycling political policies from over a century ago. In more recent times, relatively speaking, the US purchased the US Virgin Islands from Denmark for $25 million in the 1917 Treaty of the Danish West Indies. The territory since, consisting of 246.36 square kilometres in the Caribbean basin, is organised according to the 1954 Revised Organic Act of the Virgin Islands.

The US Virgin Islands elects a delegate who can participate in debates in the House of Representatives but cannot vote. The Treaty of the Danish West Indies – officially the Convention between the United States and Denmark for cession of the Danish West Indies – transferred sovereignty of the now-US Virgin Islands to the United States following a number of failed negotiations in the century prior. According to the Monroe Doctrine, in which Europe must not attempt any form of domination of the Western Hemisphere at the cost of US supremacy, the risk of Germany invading and taking control of the islands post-World War I, led both the US (under President Woodrow Wilson) and Denmark to decide the islands ought to be sold for Danish and US security purposes.

History of ambition for Greenland

The Truman administration made a formal offer of $100 million for Greenland in 1946, though this was not publicly known until 1991. The argument was that Greenland was “completely worthless to Denmark”, but “control of Greenland is indispensable to the safety of the US”. Denmark declined the offer and then, as now, neither wants to sell Greenland, nor negotiate any form of sovereignty that has not been endorsed by the people of Greenland. A 2025 January poll indicated that 85 per cent of Greenlanders did not want their island to become part of the US.

On 7 January 2026, the White House issued a statement, claiming:  “It’s vital to deter our adversaries in the Arctic region. The ‍president and his team are discussing a range of options to pursue this important ‌foreign policy goal.”

It added: “Of course, utilising the ‌US military is ‍always an option at the commander-in-chief’s disposal.”

The fallout from the malevolent, if vague, statement and several speeches by both President Trump and Secretary Marco Rubio, have inflamed NATO (North Atlantic Treaty Organisation) member countries, and the Danish Prime Minister, Mette Frederiksen. She has publicly stated that an invasion would end the decades-old NATO alliance.

NATO, made up of 32 members spanning North America and Europe, was established in 1949 to form a collective self-defence against the Soviet Union, originally.

Professor Saul says, “If they were sensible, the Europeans and Australians would forge a new security and defence policy that is independent of the US, to safeguard against the grave danger to international and national peace and security posed by the US.”

Dr Elizabeth Buchanan, from the Australian Strategic Policy Institute, told the ABC that the reason the US, Russia and China are interested in Greenland is owing to its geographic value in terms of trade and security. In December last year, ASPI launched Australia’s first polar security program.

As Buchanan wrote for the ASPI website, “In both the Arctic and Antarctic, the boundaries between science, strategy and sovereignty have blurred. In the north, melting sea ice has opened new trade routes and created fresh opportunities for resource extraction, drawing renewed attention from the United States, Russia, China and NATO. The Arctic is rapidly becoming a testing ground for uncrewed systems, satellite networks and undersea monitoring—technologies that blend civilian and military use.”

The US administration revealed its National Security Strategy in December, which prioritised US dominance over the Western Hemisphere (a hark back to the Monroe Doctrine). This proposal to buy Greenland, or to take it by military force, fits with the priorities of this strategy.

European reaction

Denmark and allies – the leaders of France, Britain, Germany, Italy, Poland, and Spain – issued a significantly less bellicose response in the form of a joint statement, reminding the US of its position as a NATO ally.

The statement read: “Greenland belongs to its people. It is for Denmark and Greenland, and them only, to decide on matters concerning Denmark and Greenland … NATO has made clear that the Arctic region is a priority and European Allies are stepping up.”

Russia and China, already inconvenienced by the US takeover of Venezuelan oil reserves and stymying of the shadow fleet, have not responded publicly. Yet, on 4 January, Trump told media, “Right now, Greenland is covered with Russian and Chinese ships all over the place. We need Greenland from the standpoint of national security.”

As reported by Al Jazeera, vessel tracking data from maritime data and intelligence websites such as MarineTraffic do not show the presence of Chinese or Russian ships near Greenland.

Nonetheless, Trump’s concerns that China and Russia have designs on the Arctic region are valid. As the ice melts due to global warming, the Northern Sea Route (NSR) in the Arctic Ocean provides an economical means of shortening shipping trips. The NSR provides Russia with a more direct trade route with Asia, necessary owing to Western sanctions. According to Al Jazeera, the number of oil shipments from Russia to China via the NSR rose by a quarter in 2025.

On 4 January, Prime Minister Mette Frederiksen countered that: “It makes absolutely no sense to talk about the US needing to take over Greenland. The US has no right to annex any of the three countries in the Danish kingdom,” she said, alluding to the Faroe Islands, which, like Greenland, are also a Danish territory. I would therefore strongly urge the US to stop the threats against a historically close ally and against another country and another people who have very clearly said that they are not for sale.”

Denmark has been hospitable to a US military presence in Greenland. In December 2023 (under the Biden administration), a US-Denmark agreement was signed, in force since 2024, which provided the US unhindered access to Danish airbases, a right echoed in agreements with Sweden, Finland and Norway.

The deal, as reported by The Guardian, provides for US soldiers to operate under US jurisdiction in Denmark, access Danish airbases in three Danish cities – Karup, Skrydstrup and Aalborg – and exercise military police powers over Danish civilians at, and outside, these locations. Further, the US is empowered to carry out military activities in and from Denmark.

The most likely scenario is that the US negotiates a Compact of Free Association. Under such, the Federated States of Micronesia (FSM), Republic of the Marshall Islands (RMI), and Republic of Palau all have their own governments, but the US has responsibility for their defence and foreign affairs. Closer to home, New Zealand has free-association arrangements with the Pacific Island nations of Cook Islands and Niue.

Professor Saul says, “There is a Compact of Free Association, an agreement, between the US and three Pacific Island states (Micronesia,  Marshall Islands, Palau) that recognises their independence while establishing a special relationship with the US, which provides economic aid, immigration rights in the US, and security, in return for giving the US exclusive military access.”

Signal to others

As speculation in the media circles over whether Trump’s proposed purchase or military invasion to take Greenland forcibly gives licence to China to do the same in Taiwan, or for Putin to maintain Russia’s occupation of Ukraine, LSJ Online asked Professor Saul whether this was a genuine concern, or whether it could it have the opposite effect where China takes the opportunity to position itself as the upstanding alternative trade/security/economic partner of Asia, Europe, and Africa.

“It would seriously erode the prohibitions on the use of force and the conquest of foreign territory and signal to other countries that they can behave similarly if they have the power to do so,” he says. “Legally, Taiwan is in a different situation because of its historical links to China. At the same time China could well appeal to many states as the ‘adult’ of the international system when faced with the unpredictability, unreliability, and destructiveness of the US under Trump.”

On 12 January, the Danish Prime Minister said, “This is a decisive moment.” On Facebook, she added, “We are ready to defend our values – wherever it is necessary – also in the Arctic. We believe in international law and in peoples’ right to self-determination.”

Germany and Sweden publicly supported Denmark against Trump’s repeated claims to Greenland. Swedish Prime Minister Ulf Kristersson labelled Trump’s claims as “threatening rhetoric”.

“Sweden, the Nordic countries, the Baltic states, and several major European countries stand together with our Danish friends,” Kristersson told a defence conference in Salen. Kristersson said a US takeover of mineral-rich Greenland would be “a violation of international law, and risks encouraging other countries to act in exactly the same way”.

As reported by the BBC on 10 January, Greenland citizens firmly oppose a US takeover. Journalist Katya Adler, in Nuuk, recounted:

“One pensioner banged his walking stick on the ground in emphasis as he told me the US must never plant its flag in Greenland’s capital.

“A lady who said she was mistrustful of everyone these days, and didn’t give her name, admitted she was ‘scared to death’ about the prospect of Trump taking the island by force after she watched his military intervention in Venezuela.”