After news leaked last week that President Trump had expressed interest in acquiring Greenland from Denmark, his critics predictably derided him as crazy. But once again, the president is crazy like a fox. The acquisition of Greenland would secure vital strategic interests for the United States, economically benefit both us and Greenlanders, and would be in keeping with American — and Danish — diplomatic traditions.

Strategically positioned in the Arctic Circle, Greenland has long attracted the attention of American policymakers. As far back as 1867, Secretary of State William Seward explored the acquisition of Greenland around the time that he negotiated the purchase of Alaska from the Russians. I myself raised the prospect of acquiring Greenland with the Danish ambassador just last year.

In 1946, the Truman administration offered $100 million to Denmark to acquire Greenland, arguing that the island was “indispensable to the safety of the United States” in confronting the growing Soviet threat, just as it had been in World War II when American forces used bases in Greenland to deter Nazi aggression. While the deal didn’t go through, we kept troops on the island throughout the Cold War. Today, the Air Force’s 21st Space Wing is stationed at Thule Air Base in western Greenland to support our ballistic-missile defenses and space missions.

America is not the only nation to recognize Greenland’s strategic significance. Intent on securing a foothold in the Arctic and North America, China attempted in 2016 to purchase an old American naval base in Greenland, a move the Danish government prevented. Two years later, China was back at it, attempting to build three airports on the island, which failed only after intense lobbying of the Danes by the Trump administration.