Memes

You got me digging… Liebknecht (and others) discussed it at the 1891 SPD Reichsparteitag (available at the internet archive in hard to read German) Liebknecht warned that state capitalism was the worst form, and not true socialism … ie. don’t equate the expansion of state corporate power with socialism.

Correct, socialism isn't when the government does stuff. Bismark was not a socialist for nationalizing industry in the context of a bourgeois state with private ownership as principle.

His opinion was that even when the state owns or controls industries, the capitalist mode of production (markets, wage labour, accumulation) remains intact rather than being replaced with genuine social ownership. It was apparently a rebuttal to “state socialism as reformist ideology”, asserting that merely placing capital in state hands does not abolish exploitation, and could even be a harsher form of it.

This is the difference between state capitalism and a socialist market economy, ie between a state ruled by capitalists with private ownership as principle yet strong state control (Nazi Germany, the Republic of Korea, US Empire, etc) vs one where public ownership is the principle aspect of the economy and the working class in control of the state and markets for smaller and medium firms, ie PRC and Vietnam.

That was at a time when there were no socialist states.

Sure.

Lenin apparently turned it on its head, declaring that the state can be proletarian and not bourgeois, and that state capitalism under a proletarian state is a step forward, not backwards.

Lenin did not turn this on its head. Lenin corrected the Second International, who were reconciling a bourgeois state with "socialism," ie social democracy or state capitalism. The state can be proletarian, correct, this is true since Marx and Engels theorized about the state, and it is the proletarian state that withers away.

By Liebknechts criteria, china has state capitalism (and not socialism, which he treated as mutually exclusive)

Incorrect, see my point distinguishing state capitalism with socialist market economies.

And China would probably fail Lenin’s own conditions for socialist transition, because China presents state capitalism as a stable system and not a transitional one (ie. as a means, not a mode).

Further incorrect. China presents its socialist market economy as the initial stages of socialism:

China calls itself socialist anyway, but it’s definitely with chinese characteristics like party control and private capital making millionaires. Healthy & peaceful criticism/discussion should be welcomed, along with recognising what they are doing well.

Socialism with Chinese Characteristics describes China's model of socialism and unique features like the Mass Line, not that private property still exists. Every socialist state in history has had some level of private property, even the DPRK, but the Marxist analysis of private property in the context of a socialist state is that it exists in a form that prepares its own socialization.

Overall, I think times change and capital ownership is an extremely practical concept that we probably won’t break away from anytime soon. Leibknechts warnings should still be heeded.

Overall, I think if you want to discuss socialist theory and whatever any given theorist would approve or disprove of, you should actually read them.