US vice-president faces difficult task of pacifying Tokyo while openly communicating with Beijing US Vice-President Joe Biden arrived in Tokyo late on Monday for the first leg of a tour of East Asia that will later take him to China and South Korea. Biden’s visit comes amid mounting tensions between China and Japan over territorial claims and China’s announcement last month of its East China Sea Air Defense Identification Zone. Biden is walking a diplomatic tightrope, according to observers, with various parties calling on him to support their stances, while others look to the US to calm tensions. Japanese Prime Minister Shinzo Abe said on Sunday that he would discuss China’s air defense…