Here is Hugh's analysis of the situation:
China has said that they won't get involved if N. Korea attacks the South. But they said they will attack if the US and the South invade the North. Kind of worrisome, really. 
If the Middle East has to put up with a nuclear armed client state of the US, Israel, then there is no legal reason for N. Korea to be punished for having nuclear weapons. 
Now, if we really meant it when we said we are on the path of nuclear disarmament for all nations, then there would be a case to stop proliferation.
If China were to get involved, there is no reason to suspect that if we drop nuclear weapons on the North, they won't expand the war...
Any summation of the dangers of a possible war that never mentions China once is kind of incomplete, remembering what happened previously.
Hugh Massengill, Eugene Oregon