But the sense of cultural and political unity had been established for two thousand years prior to that. There are plenty of regional variations in culture, but every large civilization (including Russia) has them. A standardized spoken language had already been established long before the rise of the PRC - even during the Ming Dynasty it was decided that bureaucrats should speak a standard spoken language based upon the Beijing dialect.Does the chinese soviet republic count for OTL?
Also I'd actually expect the Han SSRs to split apart very quickly in this situation. E.g. A Siuchanese SSR, a Cantonese SSR, etc etc. Han Chinese are not a unified ethnic or linguistic group they just tend to act as such or pretend to do so. Kind've like white Americans.
Even mandarin dialects are mutually unintelligible in this time period were typing in now - siuchanese vs beijing dialect is an example. Back then when the standardization was weaker it will be damn weaker and more different in dialects.
Things like ethnicity are an entirely human construct. They exist because the people believe they exist, and it's very arrogant to tell a people who have held a belief for two millennia and displayed it repeatedly that they've been acting or pretending it. It's like telling modern day Christians that Christianity isn't a real religion and they've been acting and pretending it's been one for two millennia.
China as a unified political entity has been sacred for thousands of years. Any Chinese politician cannot touch this. It would be like the President of the United States ripping up the Constitution, or the British Prime Minister ripping up the Magna Carta. Or the French President denouncing Liberté, Égalité, Fraternité as nonsense.
During Barbarossa, Sheng believed the USSR was about to collapse and aligned himself with the KMT while purging Xinjiang of Communists, even killing Mao's brother in the process. When the Soviets gained the upper hand he decided to come back to the Soviets and wrote a letter to Stalin asking him to annex Xinjiang as an SSR. In the late 1940s the Soviets supported a separatist movement which used Islamist rhetoric; when the CPC won the Civil War, the leaders of the movement flew to Beijing to participate in the new government, and the plane mysteriously crashed near Irkutsk.Didn't that happen when shicai basically gave up stalin and affiliated closer to the KMT thinking that the soviets would splice WWII?
Decades later retired KGB officers confirmed what was blindingly obvious, that Stalin colluded with Mao to order the NKVD to rid them off.
You should do some more research before making comments or posts.