In World War II’s dog-eat-dog struggle for resources, a Greenland mine launched a new world order

Greenland's cryolite mine, essential for U.S. airplane production, was below sea level and vulnerable to Nazi sabotage. Reginald Wilcox, ca. 1941. Peary–MacMillan Arctic Museum, Bowdoin College

On April 9, 1940, Nazi tanks stormed into Denmark. A month later, they blitzed into Belgium, Holland and France. As Americans grew increasingly rattled by the spreading threat, a surprising place became crucial to U.S. national security: the vast, ice-capped island of Greenland.

The island, a colony of Denmark’s at the time, was rich in mineral resources. The Nazi invasions left it and several other European colonies as international orphans.