It’s not about nuclear weapons, leverage with President Trump or the trade war.
.. Such vagueness should come as no surprise since obtaining a compromise from Mr. Kim never was the purpose of Mr. Xi’s trip. China’s president did not travel to North Korea to prove to Mr. Trump that only the Chinese government can broker a deal with Mr. Kim or to gain bargaining power in the trade dispute. In keeping with the long, tangled history of Chinese-North Korean relations, Mr. Xi traveled to Pyongyang to lure back into China’s fold what he sees as a difficult and wayward subordinate.
China may be North Korea’s largest trade partner and a formal defense-treaty ally, but tension and distrust have characterized relations between the two countries for decades. Strains reappeared in recent years after Mr. Kim tested nuclear weaponsand seemed to pull back from China while repositioning North Korea closer to the United States and South Korea. China, for its part, has gone along with the latest punishing international sanctions against North Korea.
Kim Il-sung resented the asymmetry and as a hedge maintained ties to the Soviet Union after the Sino-Soviet split in the late 1950s: He needed Mao, but didn’t think Mao could be trusted. Sure enough, come 1972, China welcomed President Richard Nixon in Beijing and began rapprochement with the United States, while North Korea remained violently opposed to the presence of the several tens of thousands of American forces stationed in South Korea.
After Mao’s death in 1976, the patterns of Chinese-North Korean diplomacy, like so much to do with China, changed. Mao’s successors were more interested in developing China’s economy than in big-power politics. In 1978, the leaders Hua Guofeng and then Deng Xiaoping made North Korea their first overseas destination. But this flurry of diplomacy belied the emergence of new tensions in the alliance: The two countries’ political systems and approaches to economics and foreign affairs began to diverge.
By the mid-1980s, China was barreling down the path of “reform and opening-up,” as the official line went, and it wanted a stable international order, thinking that this would be more conducive to its own growth. But Kim Il-sung saw China’s burgeoning links to capitalist economies as a betrayal of the socialist trading bloc, and his government is suspected of having ordered assassination attempts and terrorist attacks abroad.
Then came what the North Korean government considered to be an unforgivable act of treachery: In 1992, as Communist regimes were collapsing across Eurasia, the Chinese government normalized relations with South Korea, leaving Kim Il-sung diplomatically isolated and economically in the dust.
After Kim Il-sung’s death in 1994, his son and successor Kim Jong-il asserted some measure of independence from China by not visiting for six years. He finally made a trip in 2000, soon before hosting the South Korean president for an unprecedented meeting and while preparing to bring President Bill Clinton to Pyongyang — or, only once it seemed like détente with South Korea and the United States was within grasp.
Several Chinese leaders, in turn, visited Pyongyang in the early 2000s, trying to project the image of a special relationship. Yet something was resolutely changing: The North Korean government was now doggedly pursuing a nuclear weapons capability, not only to defend itself against the threat of regime change suddenly posed by a hostile Bush administration, but also to emancipate itself from its unreliable and bossy ally.