For the record I hope this crisis does not escalate and is quickly and peacefully resolved. However the situation is very complex and we must look at the entire history of the divided Korea and not just the last few months in order to analyze it properly.
Many here think, and I can understand why they do that it would be best if the leadership of North Korea could be overthrown and Korea reunified. However many in the west thought the same thing in the 1950's and in the end a war occurred which caused millions of casualties but ended in a stalemate without a peace treaty between the north and south leaving them in a state of war which persists until the present day. The only thing in place which is preventing hostilities is a cease fire agreement.
A couple of people in this thread have indicated that China would stay out of it and that they have no reason to help the North. It is my belief that if the South with the support of the west starts a war China will intervene, if only to preserve a buffer between itself and the US military. Keep in mind that South Korea still hosts US troops and that the number of those troops can always be increased. In any case I can see China being vehemently opposed to US forces being stationed in the North in case of reunification.
I believe that the best course of action is to have a peaceful resolution. However if the west along with South Korea decide to remove the North's leadership they will have to sit down with China and work out an arrangement whereby the North would be demilitarized. If unilateral action is taken I believe there will be dire consequences not only for the region but for the rest of the world both in the economic and security respects.
