What Kim Jong Un did in China was show the international community that they were actually serious about bringing an end to their nuclear weapons program. China is by far the biggest ally that North Korea has. China is also one of the more respected if not the most respected countries in the world. If Un is able to show the international community that they are actually serious about ending their nuclear program then they will most certainly open the door for more and more countries dropping sanctions and a whole new respect will be shown to the country.
What Kim Jong Un done in China was to consult and confer with a country that had their best interests in mind. It was in China that Kim Jong Un first showed that he was very serious about changing and bringing a more brighter future to North Korea. It could be one where North Korea could have as much respect as any other country. What Kim Jong Un done in China was show that North Korea was serious about becoming a respected member in the international community.