On Christmas Day 1991, the Soviet Union collapsed, and the Cold War came to an end. Beijing wasn’t celebrating.

While one Cold War was ending, another was beginning. China’s communist rulers watched with alarm as their rival’s rule came to such an ignominious end. The Soviet Union had been integral to the rise and eventual victory of the Chinese Communist Party after the country’s nearly two-decade-long civil war. But the two powers eventually became rivals, fighting to be the preeminent power in the communist world.