Greenland must make its own decisions about independence from Denmark, Prime Minister Mette Frederiksen told President-elect Trump in a Wednesday phone call. The big picture: Trump, since his first term, has repeatedly floated the idea of the U.S. buying Greenland even though the island's leaders have said it is not for sale.

Some of Trumps threats to take over Greenland, Canada, and the Panama Canal are based on actual U.S. strategic goals. Others are just idiotic.