Adrian Hong outlines a strategy for ending Kim Jong-Eun's reign before it gets going:
[P]ressure is still the key. Western nations, in conjunction with China and Russia, should overtly offer senior DPRK leadership asylum in exchange for defection, while pursuing action at the International Criminal Court against senior leadership implicated in crimes against humanity. Although distasteful, efforts should be made to pledge immunity from prosecution for key leaders in exchange for going into exile.
Dan Trombly is aghast:
[E]very single attempted North Korean uprising has been met with lethal force.
… Even if a mixture of bought-off [Korean People's Army] generals, dissidents reinfiltrated across the border, and spontaneously invigorated Korean people was able to coalesce into a serious fighting force, the regime would likely retain enough support to militarily crush such a rebellion, and would be able to use its nuclear weapons to ward off any kind of foreign military intervention. While the KPA is hardly a perfect military, the Kim family regime’s Songun policies put the strengthening of the military force first. Contrast this to Gaddafi’s explicit weakening of the military and reliance on a variety of security services, mercenaries, and local paramilitaries, and one can see why the KPA would be a much more formidable fighting force for an incipient revolution to confront.
Based on optimistic assumptions about how a collapse might occur, we estimate that 260,000–400,000 ground force personnel would be required to stabilize North Korea. This means that even in the relatively benign scenario that we describe, the requirements for stabilizing a collapsed North Korea would outpace the combined U.S. troop commitments to Iraq and Afghanistan.