On March 25, the North Korean leader Kim Jong-un arrived in Beijing in an armored train for talks with Chinese Communist Party Secretary Xi Jinping, the first known time he traveled outside his country since his father and predecessor died in December 2011. The visit was a bombshell: Relations between Beijing and Pyongyang had soured in recent years as the Chinese became more exacting in implementing economic sanctions against the North Korean regime. In his talks with Kim, Xi seemed willing to turn the page. He highlighted the history of “close exchanges” between China and North Korea, and the time when the leaders of the two countries were “like relatives.”