Why Trump's push for frigid Greenland is about icing out US adversaries

President Donald Trump has insisted the U.S. needs to "get" Greenland, "one way or another." But it’s not the first time U.S. leaders have had their eyes on the icy, sprawling island.

Located in the middle of contested waters between the U.S., Russia and Western Europe, Greenland is situated at a point that could protect the North Atlantic passage from Russian ships and submarines. It was a key military vantage point during the Cold War, and President Harry Truman offered to buy Greenland from the Danes in 1946. 

The island is also a transfer point for communication cables that cross the Atlantic. European officials claim Russian "ghost ships" have been destroying such cables by dropping their anchors and dragging them across the ocean floor.

Greater control over...