By Mariana Goldsmit Valdespino
Last block, I found myself sitting in a Global Security lecture staring at a slide reading “Let’s play a war game: what would a Chinese invasion of Taiwan look like?” For the next hour, the professor went through different scenarios of what would happen if China decided to invade Taiwan, considering everything from the actual military plans to the geopolitical consequences. About a week after that class, President Trump started thinking about his own Taiwan adventure, but this time in Greenland. So I thought that we Spilers could play our own war game and find out what an American invasion of Greenland would look like.
Why does Trump care about Greenland?
So before we go into the different scenarios for what, at the moment, appears to be a far-fetched possible invasion, let’s look at the background behind Trump’s intentions. Though it had previously received little attention within academic circles, Greenland, the world’s largest island, has always been highly regarded among American politicians. Why? Because, as Marc Jacobsen, associate professor at the Royal Danish Defence College, explains if Russia was ever to deploy nuclear weapons to the United States (US), it would do so through the North Pole and Greenland. Thus, military control over the island would give the US a significant defensive advantage over its biggest historical adversary.
In fact, this is not the first time the US has tried to obtain Greenland. The first attempt to acquire Greenland came in 1867 following the American purchase of Alaska. Afterwards, in 1946, President Truman offered $1.2bn USD for the arctic territory, but the Danish government refused to sell. Finally, Trump himself tried to buy the island during his first term in 2019, but this time both the Danish and Greenlandic governments refused, stating that “Greenland is not for sale”.
In addition to its strategic advantage, Greenland could also present an economic opportunity for the US if it were to control it. Currently, 80% of Greenland is covered with ice. However, as the planet continues to heat up and Greenland’s ice cap melts it will open up a massive reserve of oil and rare earth minerals, including 25 out of the 34 resources in the European Union’s (EU) critical raw materials list. Today, the US heavily relies on China, with whom Trump recently started a tariff war, for access to these resources. So, Greenland could offer a less costly alternative and great move towards self-sufficiency.
A one-sided military match-up
The US has by far the largest military in the planet, and Donald Trump didn’t rule out using it to invade their northern neighbor. In 2024, the US spent $948bn USD in military spending and has 1.3 million military personnel. In contrast Denmark, whom Greenland is a part of, spent only $9.9bn and has only 17,000 soldiers. This difference is so big that, as professor Kristian Søby Kristensen explains, even Denmark has “always known that it cannot defend Greenland against anybody on its own”. That is why, in 1951 they signed an executive agreement with the US where the latter pledged to protect the island against any attack. Whether this included an attack perpetrated by itself is what keeps puzzling academics like Kristensen, who said that the real question is who the Americans would fight in case of an invasion. “[Would they fight] their own military? They’re [the ones] already there”, he told Politico.
Even though Denmark has exponentially increased their defensive spending as a result of the war in Ukraine, dedicating 2.37% of their GDP to military expenditure and replacing all of their F16 fighter jets with more advanced F35s, it would still be practically impossible for it to militarily stop an American invasion of Greenland on its own. This is such a mismatched relationship that Ulrik Pram Gad from the Danish Institute for International Studies called this hypothetical invasion “the shortest war in the world”. This is further strengthened by the fact that, at the moment, the vast majority of the military personnel stationed in Greenland is also American, with the Pituffik Space Base being a crucial station for the US military.
As for what that invasion would actually look like, it would most likely be fought by air and sea as Greenland’s icy terrain is strategically complicated to operate in. However, as previously mentioned, the US currently has more military personnel on the island than Denmark itself. So, we’re basically predicting what it would be like for them to invade a territory they themselves control. What we can determine though, is how long that invasion would need to take, at least on paper. Legally speaking, Trump’s administration would need to notify Congress of any military move within the 48 hours following the commitment of armed forces, that is if Pete Hegseth hasn’t already added them to the group chat (just kidding). After that, Congress would need to authorise the use of force or declare war against Greenland, both highly unlikely scenarios. For this to happen, Trump would require at least 66 votes in favor of going to war, and with the Democrats holding 45 seats (compared to 53 by the Republicans) this would be very complicated. In the case that Trump doesn’t receive the authorization he would be required by Article 1.8 of the US Constitution to end all military operations in Greenland within the next 60 days. This, however, seems like more than enough time for the US to secure control over Greenland.
So Denmark definitely can’t stop an American invasion by themselves, at least militarily. Yet, they are members of both NATO and the EU. Does that mean they might not have to do it alone?
NATO
What happens when a NATO member invades another member? In practice, not much. The most famous article in the North Atlantic Treaty is probably Article 5, which states that “an attack over one member is an attack on all”. However, for this article to be enacted, as all other decisions taken by the North Atlantic Council (NAC), a unanimous consensus is needed. This means that in case a member state invaded another member, the aggressor would also have to agree for all the other members to respond against it, something that, logically, will never happen. This has actually been seen before, when Greece and Turkey (both NATO members) fought against each other in the 1974 Cyprus Crisis, without the invocation of Article 5.
Nonetheless, enacting Article 5 is not the first step taken within NATO. Instead, as Norway’s Minister of Foreign Affairs Espen Barth Eide said, NATO’s involvement during a US invasion of Greenland would probably end with Art. 1, which calls for a peaceful settlement of disputes and parties refraining from the use of force. Thus, any conflict would probably be internally solved through diplomatic means.
However, many experts are not so optimistic. Instead, they argue that any internal conflict would undoubtedly diminish the Alliance’s importance and create an internal crisis. Furthermore, some of these academics and journalists think it is important to analyze the possibility of a NATO member being expelled or suspended from the Alliance.
Unlike the majority of international organizations, such as the United Nations (Articles 5 and 6) or the EU (Article 7), NATO does not have a clause for the suspension or expulsion of a member. Nonetheless, the idea was thoroughly discussed during the writing of the Washington Treaty in 1948. Arguing that NATO was more than just a military alliance, but a collective based on the principles of upholding and protecting shared values, namely democracy, individual liberties, and the rule of law, Canada proposed the inclusion of a suspension clause in case any member deviated from these ideals. Other members were wary of this, believing that the inclusion of voting into the NAC was too complicated and unnecessary. Thus, the clause was never included.
However, since then, politicians and NATO officials have constantly commented on the possibility of kicking a member out despite the lack of an expulsion clause. They argue that upholding the values that NATO is based on is a fundamental part of the Alliance’s objective (the other major part of NATO’s purpose being the protection of peace and security). Therefore, following Article 60 of the Vienna Convention on the Law of Treaties, a failure to uphold these ideals may constitute a material breach of the treaty. Article 60(b) of the Vienna convention states that a material breach consists of: “the violation of a provision essential to the accomplishment of the object or purpose of the treaty”. If this were the case, the NAC could vote to expel a member, a decision for which it would need a unanimous decision excluding the defaulting state. This means that the US would not participate in this vote.
The question of determining if the US is in material breach of its commitments under the North Atlantic Treaty is up to the other members of the Council to decide. However, if the whole purpose of NATO is to preserve peace and security, starting a war seems to clearly go against that, especially if it’s against another member of the Alliance. The same could be said regarding NATO’s founding values, as an invasion would disregard the democratic processes in Greenland (as opposed to a sale that would require a successful referendum), would be illegal, and might infringe on the individual liberties of Greenlanders. In the past, all discussions about the possibility of removing a member have been framed in a very specific discourse where the US is the one doing the kicking out. This was the case when assessing Turkey’s membership after the Cyprus Crisis and Operation Peace Spring. Thus, it remains unclear if members could and would be willing to kick out the largest member and highest contributor of the alliance. This would deal a significant blow to NATO’s international reputation, budget, and operational capacity, especially considering the US’ role as depository state and de facto leader of the organization. Additionally, as Federica Fazio from the Brexit Institute put it, the fact that the “very country NATO has relied on for protection over the last 75 yeast would now be the one it would need protection from … could trigger an identity crisis” for the Alliance as a whole. So while it would be legally possible for NATO to kick out the US, the question of whether or not it would be politically beneficial remains open.
If not NATO, could Denmark turn to the EU?
Like NATO, the European Union also has a mutual assistance clause. This is Article 42.7 of the Treaty of the European Union (TEU), which states that all members must provide assistance to any member victim of an aggression. However, whether or not Denmark would be able to invoke Article 42.7 is a puzzling question. The article reads that, in order for it to be enacted, a member state must be a victim of armed aggression “on its territory”. But it is unclear if Greenland would count as part of Denmark’s territory or not. Greenland, like the Faroe Islands, is one of Denmark’s overseas territories. Yet, the EU considers two different types of overseas territories: Outermost Regions (ORs) and Overseas Countries and Territories (OCTs). ORs are “fully-fledged EU regions subject to EU law and all rights and obligations that come with being an EU member”. Meanwhile, OCTs are territories associated with the EU but are not a part of it. Though their foreign, security and military policies often fall under the jurisdiction of an EU member (in this case Denmark), EU law does not apply to them. At first, Greenland joined the European Community in 1973 alongside Denmark, being considered an OR at this point. But it later withdrew in 1985 after a referendum. Since then, it has been considered by the EU as an OCT, which some argue excludes them from being covered by Art. 42.7. This argument states that the clause should only cover ORs where EU law is applicable. Nonetheless, the French Minister of Foreign Affairs Jean-Noël Barrot recently suggested that the status of ORs and OCTs is not fixed and Greenland’s status could be modified by the European Council if Denmark requests it. In that case, Denmark could invoke Art. 42.7, a move for which they would not need unanimity.
Though the decision to invoke does not need to be unanimous, it will probably only result in bilateral assistance to Greenland and fragmentation within the EU. This is because the EU lacks a sanctioning mechanism that would force member states to comply, and it is easy to expect countries like Hungary and Italy to choose not to. Thus, the members who do decide to assist Denmark would need to do so through bilateral negotiations. Additionally, countries who are a member of NATO and the EU would face conflicting assistance requests, from Denmark through the EU and the US through NATO. This might lead to some political debate/contradictions within these country’s governments, but it would be safe to assume that they would commit to the assistance already provided to Denmark under the EU’s Art. 42.7. If big members of the EU, such as France and Germany, pledge to assist Denmark, it may be enough to deter further military advancements by the US.
Other possible (non-military) scenarios
In addition to investigating the possibility of a military invasion, we should also look at alternative non-military scenarios. There’s three main non-military approaches Donald Trump could take with regards to Greenland.
Firstly, he could attempt to gain control of the island economically, as he will try to do with Canada. At first, the President threatened to impose harsh tariffs only on a few selected countries, including both Denmark and Canada. It was believed that he was doing this to try to squeeze some concessions on Greenland out of Denmark, particularly certain exclusive contracts on its soon to be accessible minerals. And if he had stuck to just a few selective tariffs, it might have worked in advancing his Greenlandic ambitions. However, as we now know, that didn’t happen and now his tariffs present two main flaws towards the achievement of this goal. First of all, he did not just impose tariffs on Denmark, but slapped about 90 different countries with his “reciprocal tariffs”, including the entire EU. This gives Denmark no further incentive to negotiate with Trump as it would have to do so alongside the entire European block and it appears to be just one of many affected countries with no special interests to Trump. Furthermore, Trump’s tariffs leave out pharmaceutical products. Currently, Denmark’s largest exporting sector is big pharma, particularly through the production of insulin and weight-loss drug Ozempic. Thus, while the tariffs will definitely affect Denmark, as every other country with tariffs, they will not have the strongest effect on its economy, leaving the largest sector untouched. This, once again, limits Denmark’s incentives for further negotiations with Trump on alleviating these tariffs.
The second possible scenario is for Greenland to become independent. Independence has been a long-standing issue amongst Greenlanders, with recent polls showing that about 80% of them would support independence from Denmark. Additionally, the Danish government has given the understanding that, if Greenland were to pass a referendum calling for independence, they would accept and ratify it. Yet such independence may not come anytime soon. The main problem is that, at the moment, Greenland heavily depends on subsidies from Denmark. Today, those subsidies account for about ⅕ of Greenland’s entire GDP and are used to pay for Greenlanders’ education and health care. So unless Denmark agrees to continue paying for the subsidies, in an agreement similar to what the US has with Puerto Rico, the calls for independence are not expected to go far. Nonetheless, Denmark is not the only one who could potentially pay for those subsidies, and there have been discussions about having the US take over that annual $800 million USD expense or even lease the land from Denmark. For these options to happen, there would need to be approval from both Denmark and Greenland. While we don’t exactly know where Denmark would stand on the issue, Greenland has made it pretty clear that they have no interest in becoming Trump’s 51st state, with a January opinion poll showing 85% of Greenlanders rejecting the idea and only 6% wanting to be part of the US (everyone else was undecided). In fact, the most likely case is that Trump’s public interest in the island only pushes the independence debate in the opposite direction. This is because, even though we have shown that the possibilities of the EU or NATO taking decisive action in case of an invasion are low, they are certainly still there. And as long as Trump maintains his aggressive discourse towards the icy land, Greenlanders would want to have at least some degree of extra security.
The final scenario, which in my opinion is the most plausible, is that Trump simply loses interest in Greenland. Donald Trump’s second presidential term has lasted a little over three months (though it feels much longer), but every one of those days “have been nothing short of dizzying”. Filled with chaos and indecision, the Trump administration has announced, unannounced, enacted and halted dozens of different policy proposals. Perhaps the most obvious example of this can be seen in his “reciprocal tariffs”. The President first promised to place tariffs on Mexico and Canada during his inaugural speech on January 20th, stating they would go into effect by February 1st. However, since then, he has postponed the tariffs on his two neighbours twice, exempted various products, even lowered the percentage, and, to this day, most tariffs have still not been imposed on Mexico. Something similar can be seen in his approach to tariffs on China, saying on Tuesday that the tariffs “will come down substantially”. Another key example of Trump losing interest or going back on a policy promise can be seen on his intentions to retake the Panama Canal. Alongside annexing Canada and Greenland, this was one of the major announcements he made as soon as he was inaugurated. Yet, January is also when his Panama intentions ended, with him barely mentioning it again afterwards. Though this might be because he has been extremely busy with other things (you know, destroying the global economy and so forth), it is probably because his advisors realized that reclaiming the canal is more complicated than he thought. Thus, abandoning the idea altogether was simply easier. Many political scientists and journalists expect a similar pattern with regards to his views on Greenland, where he will either notice the impracticalities of his plan or simply find a new toy to take.
These are just some of the possible legal and military processes an American invasion of Greenland would trigger. Though this military match-up presents almost an immediate American victory, an invasion of Greenland could trigger a number of legal processes that, while probably not starting a war against the US, will certainly damage its reputation within the international community and NATO’s standing in global security. Not to mention the incredible doubt it would seed on every Western country relying on American protection from their respective adversaries. Nonetheless, at the moment, the idea still seems incredibly far-fetched, even for this Trump administration. So, hopefully it all remains as nothing more than a fun little twisted game.
Photo: Felix Mittermeier via Unsplash
