Trump Is Finding China’s Blind Spot on North Korea

Beijing’s opposition to a missile-defense system in South Korea hinders working with U.S. to crimp Pyongyang.

Amid steadily mounting international tension over North Korea’s nuclear and missile programs, the key question is this: Is China serious about working with the U.S. to crank up the pressure on Pyongyang?

In an Oval Office interview with The Wall Street Journal last week, President Donald Trump seemed cautiously optimistic that the answer will be yes. He cited signs the Chinese are at least starting to squeeze North Korea economically. He then reiterated that statement of optimism Sunday in, characteristically, a tweet.

But here’s a real, less obvious test of whether China is serious about working with the new American president to hem in North Korea: Will China stop resisting the installation of a new missile-defense system in South Korea?

On that count, the Chinese still are coming up short. On Monday, two days after the North Koreans staged a provocative military parade of the missiles it is developing, and just hours after they staged a failed test of one such missile, the Chinese foreign ministry reiterated China’s opposition to putting an American-built missile-defense system in South Korea.

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