Second, China wants to keep a zany North Korea as a buffer state.

FORBES: Magazine Article

It has propped up the Kims, if only to protect the buffer state that separates it from the American troops garrisoned in South Korea.

ECONOMIST: North Korea��s nuclear weapons

When India was allied with the Soviet Union, China and the United States supported Pakistan as a buffer state, reinforcing the neighbors' historical rivalry.

CNN: GIVE PEACE A CHANCE

China has wanted to keep the North as a client and buffer state, but this may be a moment when it too begins to rethink its interests in Pyongyang.

WSJ: Review & Outlook: Breaking the Kim Dynasty

In that despatch Mr Chun reportedly says some Chinese officials were willing to "face the new reality" that North Korea was of little value to China as a buffer state.

BBC: Rare insight into secretive China-N Korea ties