http://themoderatevoice.com/34898/what-do-north-korea-and-china-want/WHAT DO NORTH KOREA AND CHINA WANT?
<snip>What purpose does North Korea have in developing such military technology? One merely has to look south to the advanced country on the Korean Peninsula protected for nearly 5 decades by a significant presence of U.S. military forces. Since 1953 both Koreas have believed the dividing line along the 38th parallel to be an artificial but imposed separation between the developed, modern world, and a truly backwards totalitarian regime. The Korean division is solely the result of a 1953 military standoff between Chinese and American troops in which neither party wanted to escalate or continue the conflict.
Kim Jong-Il believes he will be the first President of a unified Korea. For five decades he has not had the conventional military strength or civilian support to change the dynamics on the ground. During the past decade, he decided to pursue an aggressive path to change the balance of power on the Korean peninsula. Though it would be ugly, bloody and difficult, any military match only between the two Koreas would be an outright loss for Jong-Il so his Chinese protection over the past 6 decades has been essential for his very survival.
The reason China doesn’t care about the crazy North Korean regime is that Jong-Il has probably assured Chinese leaders that his ultimate goal is similar to theirs: the removal of all U.S. troops from the peninsula protecting the South. The Chinese government could not care less about what types of despotic regimes are along its borders. China views most of Asia as its natural and rightful sphere of influence and control. snip
The Chinese might know of and secretly support this overall plan to ensure that U.S. troops are withdrawn from its natural sphere of influence and control. China would also get a measure of pleasure in seeing the U.S. humiliated again, and it would be able to assert itself as a true world power via proxy. Once reunification is achieved, the many North Korean refugees in China could leave and arguably the peninsula would no longer need any nuclear weapons. Then China could dictate the future of Kim Jong-Il and Korea according to its own best interests.
North Korea and China know what happened in Vietnam. The U.S. decided to leave when it realized it was supporting the weakest party to a civil war, and that it had no real strategic national interest in that country. Eventually the South Vietnamese did not have the desire to defend a completely corrupt and incompetent regime, and Americans could not see losing more lives in that same pursuit either. The plurality in the South viewed reunification, even under the communist North, as better than continuing a decades-long bloody civil conflict.