In August 2019, the President of the United States, Donald Trump, has expressed his interest to buy Greenland from Denmark. To the proposal of buying the world’s largest island, which is an autonomous Danish territory, the Danish Prime Minister, Mette Frederiksen, has promptly replied that “Greenland is not for sale”.
Donald Trump is not the first person to express interest in buying Greenland. In 1946, at the beginning of the Cold War, Harry S. Truman offered 100 million of dollars to Denmark to obtain the control over the territory. Denmark did not accept the offer but, in 1951, a defense treaty was signed between Denmark and the United States, giving the U.S. military rights over the Thule Air Base in northern Greenland.
Why so much interest towards Greenland? Located between the North Atlantic and the Arctic oceans, Greenland holds an inestimable geo-strategical position; not to mention Greenland’s natural resources, which include diamonds, gold, uranium and oil.
Historically, States have been acquired territories through war or through financial agreements. This would not be the first time that the United States buy or cede territories: in 1803, the USA bought Louisiana from France for 15 millions of dollars and, in 1867, they bought Alaska from Russia for 7.2 million of dollars. Moreover, in 1917, the United States bought from Denmark the territory of West Indies, today known as U.S. Virgin Islands. On the other hand, during the XIX century, the United States ceded some areas that are now part of Canada, as part of larger deals with Great Britain.
What does international law say in this regard? Can countries exchange sovereign territories consistently with the principle of self-determination?
In a 2017 paper, two Duke University law professors, Joseph Blocher and Mitu Gulati, discussed what it would take to create a market of sovereign territories and what problems it would solve. They argued that, according to today’s international law, it is possible for two States to sign an international treaty, ceding and acquiring parts of territory, as long as the transfer is not forced..
Buying and selling territories is an obsolete notion in the modern world but Blocher and Gulati argued over the possibility of taking the population’s desires into consideration. Their paper reads: “across the world, many regions are located in the wrong nations – wrong in the sense that the people of these regions believe they would be safer, happier, and wealthier if surrounded by different borders and governed by different leaders”, “(…) we ask how international law could help ameliorate the bad-government problem by facilitating welfare-enhancing border changes”. In this regard, they propose to change international law so that “parent nations” cannot forbid a region to secede, but they are entitled to compensation for lost territory.
In order to be valid, it is required that the transaction is in compliance with the constitutional principles of both States. The latter remark constitutes the main obstacle to the market of sovereign territories, as far as the majority of countries in the world consider territorial integrity as a constitutional foundation.
Another point to be examined is the principle of self-determination. Greenland does not enjoy a right to self-determination, due to the fact that Greenland is not registered in the United Nations list of Non-Self-Governing Territories. The register of Non-Self-Governing Territories is a list of places that the UN General Assembly deems to be “non-self-governing” and subject to decolonization process (i.e. Western Sahara, Falkland Islands, Gibraltar, etc)..
On the other hand, Greenland enjoys a high level of autonomy and the opinion of its inhabitants must be taken into account before any transaction is agreed. As regards to the regime of independence enjoyed by Greenland, it is important to underline that the latter is not a part of the European Union, even though Denmark is an EU Member State.
The Greenland Home Rule Act, approved by the Danish parliament, gives its autonomous government “fundamental rights in respect of Greenland’s natural resources”. Many locals hope control over these resources eventually will form the basis of Greenland’s independence from Denmark. For this reason, it is unlikely that inhabitants would give up their current security and the prospect of independence in exchange for U.S. passports.
In conclusion, international public law does not forbid two States to cede and acquire parts of territory, both in the case of an exchange or as a unilateral act. If both nations are bound to adhere to the international treaty providing for the transaction, and no third-country makes any claim to the territory, there is no international issue. The main obstacle to the transaction is represented by the domestic law of the countries involved. Whether or not the Head of State permits the sale is a matter of the domestic law of the selling state.
In this specific case, the position of both Greenland and Denmark is clear, as the foreign minister, Ane Lone Bagger, has affirmed that: “We are open for business, but we are not for sale”.
 CNBC, “Greenland belongs to Greenland: Denmark says selling world’s largest island to US is absurd”, 18 August 2019, available at: https://www.cnbc.com/2019/08/18/greenland-belongs-to-greenland-denmark-says-selling-worlds-largest-island-to-us-is-absurd.html
 El Pais Internacional, “Trump quer comprar a Groelandia. E ele não é o primeiro”, 17 August 2019, available at: https://brasil.elpais.com/brasil/2019/08/16/internacional/1565978508_399556.html
 Brookings, “The Greenland gold rush: promise and pitfalls of Greenland’s energy and mineral resources”, 24 September 2014, available at: https://www.brookings.edu/research/the-greenland-gold-rush-promise-and-pitfalls-of-greenlands-energy-and-mineral-resources/
 BBC News Brasil, As reaçoes à ideia de Trump de comprar a Groenlandia da Dinamarca”, 16 August 2019, available at: https://noticias.r7.com/internacional/as-reacoes-a-ideia-de-trump-de-comprar-a-groenlandia-da-dinamarca-16082019
 Joseph Blocher and Mitu Gulati, “A market for sovereign control”, 66 Duke Law Journal, 797-843 (2013)
 United Nations, “The United Nations and Decolonization, Non-Self-Governing Territories”, available at:
 Act No. 577 of 29 November 1978, “The Greenland Home Rule Act”, available at: .
 Leonid Bershidsky, “Trump is not crazy to want to buy Greenland”, Bloomberg, 17 August 2019, available at:
 Reuters, “We are not for sale” – says Greenland’s foreign minister”, 16 August 2019, available at: https://www.reuters.com/article/us-usa-trump-greenland-minister/were-not-for-sale-says-greenlands-foreign-minister-idUSKCN1V60XO
Laureata in Diritto internazionale e dell’Unione Europea presso l’Università LUISS Guido Carli di Roma. Ha approfondito la conoscenza del diritto internazionale seguendo diversi corsi presso la Fordham University di New York, Peking University di Pechino, LMU di Monaco di Baviera, HSE di San Pietroburgo e Universidade da Coruna. Ha svolto tirocini e brevi esperienze di lavoro presso il Parlamento Europeo, la Commissione Europea, il Consiglio d’Europea e le Nazioni Unite.