[BeadCounter]

This other article has comments saying Jong-Nam was China’s man. So, this may not be some mild incident for the Chinese.
http://freerepublic.com/focus/f-news/3526609/posts

[TigerLikesRooster]

Kim Jong-nam had been held in reserve. He and his uncle Jang Song-taek were more in line with China such as more market-oriented economic reform. It is still unclear how serious China was to remove Kim Jong-un and install Kim Jong-nam. It does not appear that China was actively undermining Kim Jong-un. Rather they keep Kim Jong-nam around "just in case."

The recent turn of events, that is, the election of Trump, changed the situation, I think. Kim Jong-nam has been a loose end which needs to be taken care of someday, but it cannot be postponed any longer. The possibility of Kim Jong-nam installed as some anti-regime exile group is no longer as remote as it was. If you search N. Korea-related posts at FR, there is one article I posted which says that Kim Jong-un asked Kim Jong-nam to return to N. Korea voluntarily but he balked. The message was delivered to Kim Jong-nam via N. Korean diplomats who had face-to-face meeting with him this year(January and early February.) If true, this triggered the chain of actions leading to his assassination.