Donald Trump has staked his capricious claim to Greenland on the grounds of national security, access to minerals – and ‘psychological need’. But behind his fixation lies a neo-imperial mindset. Global warming has revived interest in the centuries-old legend of a Northwest Passage between the Atlantic and the Pacific. It will probably never be a viable trade route, at least not for decades or even centuries to come. Donald Trump may see Russian and Chinese ships everywhere, but they usually stick to Russian coastal waters, far from Greenland, and are bound for ports in Europe as often as Asia.