"President Franklin D. Roosevelt took a strong personal interest in Greenland's fate. On 9 April 1941, the anniversary of the German occupation, the Danish envoy Kauffmann, against the instructions of his government, signed an executive agreement with Secretary of State Cordell Hull, allowing the presence of American troops and
making Greenland a de facto United States protectorate, which served British Empire interests very well. The cryolite mine in Ivigtut was a unique asset that made it possible for Greenland to manage fairly well economically during the war. The United States supplied the island and sent patrol boats to survey the east coast of Greenland although this activity was limited by seasonal ice. The Coast Guard, in coordination with Eske Brun, created the Northeast Greenland Sledge Patrol, consisting of 15 men, many of them former hunters in the area. Their task was to patrol the coast to discover any German activity."
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