Conspiracy theories...

Random thought trying to play military strategist: Could it be that the US is goading North Korea into action because Kim Jong-Il is physically weak and there is a strategic opportunity to remove his regime from power based on some kind of intelligence provided by the CIA? The Americans seem to be pushing quite hard on this, while at the same time trying to force China's hand in dealing with it, which would commit the Chinese into taking stronger action and being geographically closer to North Korea, it would be of more risk to the Chinese than to the Americans. Therefore, if China has to act, it would stifle its steady rise to power while not having as as much consequence to the US (comparatively) and allow for them to recover and retain their hegemony over the world. Of course, there would be a great risk consider DPRK has nukes, but who knows what goes on behind closed doors and what these higher types are thinking when they strategize?