U.S.–Denmark Defence Agreement on Greenland Signed
27 April 1951
Treaty
In 1951, the United States and Denmark signed a defence agreement granting the U.S. long-term military access to Greenland while affirming Danish sovereignty. The agreement enabled construction and operation of U.S. defense installations as part of Cold War Arctic strategy.
Background
The agreement followed Denmark’s NATO accession and responded to the strategic importance of the Arctic in missile warning, air defense, and transatlantic security. Greenland’s role was incorporated into alliance planning rather than treated as a separate territorial question.
The 1951 agreement undercuts claims that U.S. security in Greenland requires territorial control. It shows that sufficiency was achieved early—and maintained—through legal and alliance mechanisms.
Legacy
The agreement established a durable model of strategic access without ownership, which continues to underpin U.S. interests in Greenland decades later.