It seems unlikely that North Korea will continue to press its aggression on its neighbour - given the pressure from both China, and America, to do otherwise. However, it is an erratic, fragile and attention-seeking state, and anything could happen. If war does break out, then it would be potentially a trigger for a "third world war" - precisely the reason why China, a rather cool and moderate customer on the world stage, all things considered, would not let that happen. Still, yet another reason why nuclear weapons in the wrong, infantile, hands, can be a bad thing. In any hands. The Republican urge to sink recent arms reduction treaties for short-term gain, in the light of rogue proliferations, appears ever more craven.