In a sign of how far China’s leaders have drifted from their revolutionary roots, the biggest shock gripping the country today is that the ruling Chinese Communist Party (CCP) might actually be socialist after all.

The shakeup centers on the phrase “common prosperity.” It was first introduced by revolutionary leader Mao Zedong but has now been taken up as the defining mantra of a new era as imagined by current strongman President Xi Jinping.

In an Aug. 17 speech to the CCP’s Central Committee for Financial and Economic Affairs—his first since the secretive, annual summer leadership conclave at the seaside town of Beidaihe—Xi declared that “Common prosperity is an essential requirement of socialism and a key feature of Chinese-style m…