Lord Riot,
Such an operation only makes sense when there is (yet in a dark shadow) a prepared and well-controlled opposition group with appropriate leader that would quicky take and hold the power. This is to avoid chaos. Otherwise, one bad fat Un would be replaced by even worse one. Looks like such an alternative is not yet ready. And anyway, it is only China who can raise such figures, not US, Russia, Europe, to say nothing about Japan and SK who are hatred by definition in NK.