The most important reason for China’s commitment to supporting the North Korean regime appears to be Pyongyang’s geopolitical value. North Korea could serve as a buffer zone between China and U.S. troops stationed in South Korea. This kind of strategic thinking led China to enter the Korean War in 1950, sending millions of troops across the Sino-Korean border to drive U.S.-led UN forces from northern territory.

However, many far-reaching changes since the Korean War have rendered the U.S. military presence on the Korean Peninsula much less menacing, which has significantly reduced North Korea’s strategic value to China.

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