I looks like King Make Believe in North Korea has finally detonated a real nuclear device. The yield, estimated at between 50 and 100 kilotons, is much too large to presume that the hermit kingdom is pulling the same trick as last year by detonating a large cache of conventional explosives. While it seems unavoidable that North Korea possesses both intermediate-range missiles and a genuine nuclear device, this still does not mean that they have a nuclear weapon. The first ever hydrogen bomb detonated by the United States was a three story tall, cryogenically cooled building. Unless China has directly given nuclear secrets over to Kim Jung-Unwell, it seems unlikely that whatever they detonated in the mountains is a deliverable weapon.
The only solution is for China to put pressure on its client state and force them to dismantle their nuclear program. No one wants North Korea to have nukes, not the US, not Russia, not China, but China doesn't want a re-unified Korea to enter into the US sphere of influence. If there was some way to ensure the continuity of the Kim regime while at the same time eliminating all nuclear weapons from the peninsula, that would be the only realistic solution to this problem that does not involve full-scale war. China has already made it very clear, in the event of a US first strike they will back the side of their puppet. However, if North Korea strikes first, China will sit on the sidelines while the US unleashes fire and fury on Fatty McAss. Either way millions will die.
The fate of the world really rests in China's hands. They alone can diffuse this crisis.