China is flexing its muscles. As the second richest economy in the world, its businessmen and politicians are involved just about everywhere in Asia, Africa and Latin America. Now, though, China is taking a big interest in a very different part of the world: the Arctic. It has started calling itself a "near-Arctic" power, even though Beijing is almost 3,000km (1,800 miles) from the Arctic Circle. It has bought or commissioned several ice-breakers - including nuclear-powered ones - to carve out new routes for its goods through the Arctic ice. And it is eyeing Greenland as a particularly useful way-station on its polar silk road.