My experience with the communists taught me something most of them do not grasp, although it can be easily deduced from the assumptions of marxism itself, especially in its leninist version.
The content of an ideology can never be known by the narrative that carries it. Instead, it can only be found in the dialectic tension between the narrative and action. If a doctrine insists on preaching good but keeps practicing evil, it is not a beautiful ideal that was betrayed in practice.
On the contrary, what defines this ideology is precisely the systemic moral ambiguity. Nazism, for example, preached racial purity, but always found a way to prove that its allies, no matter the racial roots, belonged to the “superior race”.
Does this mean that the Nazi contradicted in practice their ideology? Not at all.
It means that the ideology was racially opportunistic from the beginning, using the concept of “race” as a unifying symbol, enlarging or restricting the reach of its meaning according to the strategic and tactical needs of the moment.
Since an ideology is essentially a theoretical justification for certain actions, it should be obvious that its interpretation depends on these actions, and not solely on its verbal statements. Marx, Lenin and Stalin understood this almost by instinct, but in general not even the militants of the left, nor their critics, see that very very clearly.
The opposition between ideal and real is typical of the bourgeois way of thinking. MARXISM ABHORS IT. Where the bourgeois accuses the communist of betraying his own ideals, the communist knows that the apparent betrayal is a deep form of loyalty, and feels happy that his enemy proves incapable of seeing the unity of the opposites.
Those with “classical liberal” education, disciples of Karl Popper and all like them, will never understand SH*T about marxism.
Given a contradiction the bourgeois way of thinking seeks to SOLVE IT and get rid of it. Marxism seeks, before everything else, to deepen it and to use it as part of the broader strategy.
The problem in these matters of marxism, is that most people (and I refer to those in academy) cannot follow even a simple chain of deductions, like in the demonstration of a geometry theorem. How, then, would they be able to follow at the same time TWO opposing lines of reasoning, or even several diverging lines, which is precisely what dialectics does?
The Brazilian left claimed to be against corruption, but once in power, steals more than all the other parties put together. What defined its ideology is precisely the dialectic game of moralism and theft, both serving to the permanent concentration of party power.
Another example is the fact that the Communist Party is very comfortable in the broader territory that includes promoting capitalism to the radical statization of the means of production.