Once taboo, China listens to US contingencies on N.Korea

It was the kind of sitdown that China had long resisted: Top US officials telling Chinese counterparts how American troops would enter North Korea if the hermit regime collapsed.US Secretary of State Rex Tillerson's recent revelation that such a discussion took place would -- if true -- suggest a major shift in Chinese policy as Beijing comes under pressure to rein in its Korean War ally.For years Beijing had refused US entreaties to discuss the possible collapse of its neighbour, but top US and