Having been over and back to Korea and Japan in the past few months, I have been struck by the animosity between the countries, particularly on the Korean side. Japan and Korea are the leading democracies in Asia and have a very close trading relationship.  But in a worrying turn of events, these security allies have seen their diplomatic relationship freeze over, a full-out trade war has ensued and there are few signs of détente on the horizon.  Given the huge strategic importance of Korea and Japan as east Asian democracies, under normal circumstances, the US would step in to…