Speaking at the World Economic Forum in Davos on Wednesday, US President Donald Trump reiterated his interest in acquiring Greenland, telling an audience of global leaders that while Washington would not use military force, its strategic interest in the island was non-negotiable.
To justify his position, Trump invoked history, pointing to the United States' role in safeguarding Greenland during World War II. Recalling that period, he said that the US "saved Greenland and successfully prevented our enemies from gaining a foothold in our hemisphere".
That historical claim is partly true. Following Nazi Germany's occupation of Denmark, the United States stepped in to secure Greenland, establishing military installations that still exist today in a reduced form. What is not accurate, however, is the implication that Greenland was ever owned by the US or later "returned" to Denmark.
More significantly, Trump's version of events omits a crucial strategic reality: America's wartime presence in Greenland was not an act of pure altruism. In exchange for protection, the US gained access to one of the most valuable wartime resources on the planet - cryolite.
Today, Trump argues that Greenland's appeal lies in its untapped minerals and its potential to loosen China's grip over rare-earth supply chains vital to electronics, automobiles, and medical equipment. Eight decades ago, however, Greenland offered something even more indispensable to the war effort.
Air power was decisive in the Allied victory over the Axis powers. Producing the thousands of fighters, bombers, and transport aircraft that dominated the skies required vast quantities of aluminium. At the time, aluminium production depended heavily on cryolite, which was a mineral found in commercially viable quantities in only one place on Earth, which was Ivittuut, a small mining town in southwestern Greenland.
Natural cryolite is exceptionally rare. The Ivittuut deposit, mined continuously from 1854 until 1987, was the world's only major source. Minor traces were known elsewhere, in Spain, North America, and Russia, but none came close to matching Greenland's output.
Ivittuut itself no longer resembles the industrial hub it once was. The settlement, located near Cape Desolation, has been abandoned since around 2000.
After Denmark fell to Nazi forces in April 1940, Greenland's local leadership and Denmark's envoy to Washington, Henrik Kauffmann, leveraged control of cryolite to secure American protection. Safeguarding the mine was essential to sustaining aluminium production and, by extension, Allied air superiority.
The US State Department later acknowledged that fears of a German seizure of the mine prompted Washington to act under the Monroe Doctrine. Negotiations with the Danish government-in-exile culminated on April 9, 1941, when US Secretary of State Cordell Hull and Kauffmann signed the Agreement Relating to the Defence of Greenland, commonly known as the Hull-Kauffmann Agreement.
The pact authorised an American military presence on the island, effectively placing Greenland under US protection during the war. Notably, this occurred at a time when public opinion in the United States remained strongly opposed to entering the European conflict, sentiment that would only shift after Japan's attack on Pearl Harbour in December 1941.
The arrangement ensured uninterrupted access to cryolite. According to Smithsonian Magazine, exports surged during the war, reaching a peak of 86,000 tonnes in 1942, with most shipments destined for aluminium smelters in the US and Canada.
The impact of that supply advantage is evident in production figures. In 1942, Germany and Japan combined produced roughly 25,000 aircraft. In the same year, the United States alone manufactured more than 47,000 aircraft of all types, according to the US Army Air Forces Statistical Digest. The production gap continued to widen as the war progressed.
The strategic importance of Greenland's contribution has long been recognised by historians. As Greenland-based historian Rie Oldenburg told Smithsonian Magazine, "Without cryolite, the Allied forces would not be able to win the Battle of Britain and bomb Germany."
Yet, during his Davos address, Trump claimed that US forces bore heavy costs defending Greenland and then handed it back to Denmark on a silver platter, without receiving anything in return.
The historical record suggests otherwise. Greenland's cryolite reserves enabled the United States and its allies to outproduce their adversaries in the air, a factor that shortened the war and tilted its outcome. Far from a one-sided sacrifice, America's defence of Greenland was part of a mutually beneficial wartime bargain, one that helped put more Allied aircraft into the sky and, ultimately, helped secure victory in World War II.
