General Discussion

[A]ccording to foreign policy experts, Danish officials have been baffled by Trump’s threats to resort to military intervention to gain control of Greenland because there’s already a long-standing agreement in place for the U.S. to increase its military presence there. In 1951, the U.S. and Denmark signed a little-known defense agreement allowing the U.S. “to improve and generally to fit the area for military use” in Greenland and “construct, install, maintain, and operate facilities and equipment” there.

“This agreement is very generous, it’s very open,” Mikkel Runge Olesen, a senior researcher at the Danish Institute for International Studies in Copenhagen, told Fortune. “The U.S. would be able to achieve almost any security goal that you can imagine under that agreement.”
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Danish Prime Minister Frederiksen, citing the 1951 agreement, implored the Trump administration to stop his talk of taking over Greenland. “We already have a defense agreement between the Kingdom and the United States today, which gives the United States wide access to Greenland,” Frederiksen said in a statement over the weekend. “I would therefore strongly urge the United States to stop the threats against a historically close ally and against another country and another people who have said very clearly that they are not for sale.”