On Sept. 18, President Donald Trump announced on a Truth Social post that Denmark, Greenland and the U.S. had agreed to give the U.S. “permanent control over security and all other needs in Greenland.”
In early 2025, Trump had threatened to “take” Greenland for its strategic national defence location and mineral wealth. The island could serve as an important military base if the U.S. ever entered conflict with Russia or China. Greenland is a semi-autonomous Danish territory in the Arctic, bigger than Mexico; the island is home to fewer than 60,000 people.
Denmark and the U.S. already have a long-standing agreement allowing the U.S. to deploy forces in Greenland. During the Cold War, the U.S. had a large military presence in Greenland.
In his Truth Social post, Trump wrote that it came at “no cost to the United States.” It is unknown at this time what the scale of the planned buildup is and whether there will be any formal authority over foreign policy and resources. Last week, American soldiers were spotted surveying an airstrip in Narsarsuaq, Greenland.
Trump also claimed that the agreement would prevent Russia and China from establishing military bases in Greenland; however, since the island is North Atlantic Treaty Organization (NATO) territory, it is unlikely Russia or China would put troops there.
On Saturday, Denmark and Greenland said any agreement with the U.S. would not compromise Greenland’s sovereignty. The deal was signed Sept. 22 at the United Nations General Assembly, where Trump emphasized that the deal “greatly protects” Europe and “very much enhances NATO.”
Under the agreement, no state that is not a member of NATO can establish manned or unmanned military installations in Greenland, nor are they allowed a persistent presence of military forces in Greenland unless otherwise agreed upon. The new deal stresses the permanence of this agreement but is otherwise very similar to the 1951 agreement between the US and Denmark.
“A time of uncertainty will hopefully give way to a binding agreement that strengthens security in the Arctic and the North Atlantic, and thereby our shared security within NATO and Europe — while respecting the [Danish] Kingdom’s red lines,” Danish Foreign Affairs Minister Lars Løkke Rasmussen said in a statement posted on Facebook on Saturday.
