I think that Kim Jong-il will survive as leader of North Korea only as long as he's able to keep the military fed and happy...which is becoming more and more problematic it seems. When he's no longer able to do that, I suspect his time left in office will be very short. Militaries don't react well to leaders who don't give them their food or their paychecks, especially when the military are the only ones getting food in the country. Of course, Kim would probably choose to cede much of his power to the Chinese government in exchange for their help if it ever came to that point. I seriously doubt he's so detached from reality that he doesn't realize that a military coup would ultimately result in his execution.