Why Trump's Greenland gambit has changed everything

In a press conference this week, president-elect Trump said that he wanted to take control of Greenland and the Panama Canal - not ruling out the use of military force to do so. Oh, and Canada, but limiting himself to economic force for that job. All of it matters, but Greenland is probably the point of geopolitical tension and change that matters the most. Trump has been clearer and bolder than his predecessors in getting its importance, but his approach to tackling it could just have passed by what would have been the easiest win of his presidency. And...