I was referring to this question:

Do the people of Donetsk and Luhansk have a right to defend themselves against the Banderite regime in Kiev?

Russia entering the war at the request of the DPR and LPR is an extension of that question, when faced with a regime intent on ethnically cleansing the Donbass region the people of the DPR and LPR extended a request for support.

As for saying vanguard parties deriving their support from the people, I already explained this is not circular. The monarchy was a small class that wielded the power of the feudal state to keep the peasantry in line, and were thus entitled to vast riches.

Vanguard parties are formed from within the working classes, succeed in revolution only through mass revolt, and once taking political power in the hands of the working classes have the same class interests as the rest of the proletariat, that being collectivization of production and distribution in the hands of the socialist state. Administrators are wage laborers, not owners of capital, and thus are not a unique owning class but instead a subsection of the proletariat.

It isn't even true that people living in socialist countries perceive administration as a unique class. The majority of people who lived in Eastern European socialism regret its fall, the broad majority supported their government and played an active role in running society.