This piece in the Times explains the ruling structures and personalities of North Korea. They have just detonated a bomb which some analysts say was larger than the one dropped on Hiroshima, and a bit smaller at 20 kilotons than the 23 kiloton 'Fat Man' used on Nagasaki. They have also tested both long and short range missiles, the former can hit the South, the latter can reach Japan. No one knows whether they have minituarised their bomb so it can be put in a warhead, which may have been the point of the latest test.

One hopes the author is right in his claim that this is just a warning to the world as the regime sorts out succession problems since the 'Dear Leader' is not a well man. Apparently military action against the North Korean nuclear programme is out of the question because of the danger of clouds of radioactivity heading south towards Seoul or to Japan. The Chinese really call the shots here. On the one hand they are embarrassed by the erratic Stalinists they support, especially since starving North Koreans regularly flee to China to eat; on the other, any outside military intervention in North Korea will result in their armies going over the border to defend their client. Obama advertised himself as ready for the 2am phone call; well now he's had one......