Chinese President Xi Jinping's recent trip to South Korea was a crucial event that has not received all of the attention it deserves. Two major motives for that trip are apparent. One was to send Pyongyang a message that North Korea will pay a price for its continued defiance of China’s objections to missile and nuclear tests. Both Kim Jong-un and his father ignored Beijing’s repeated admonitions not to undertake such provocative actions. The Chinese government’s irritation at its long-time ally has been building for some time, and Xi’s decision to snub Pyongyang by not even bothering to visit the North Korean capital before or after his trip to Seoul demonstrated that the annoyance has reached new heights.