u/aimixin - originally from r/GenZhou
Was Engels a class collaborationist for proposing the idea of a proletarian-peasant could cooperate in a revolution? In fact, Trotsky did go onto make this very argument and said the Comintern were evil class collaborationists for this.
What Lenin and Stalin had argued is that working with other classes is not inherently wrong as long as the proletariat maintains a leadership position. The alliance is not equal, the peasantry could not be the leading force in the revolution, but that doesn't mean they can't work together when they share common interests.
The reason Engels, Lenin, and Stalin all defended this viewpoint was because it made sense given their material conditions. They couldn't just wave a magic wand and abolish the peasantry because they were part of the material foundations of the economic system, and so you had to work with them when possible. Mao also defended working with the peasantry and the national bourgeoisie during socialist construction and was really only opposed to working with foreign bourgeoisie and landlords.
Economic planning is founded on public ownership, public ownership is founded on incredibly large-scale production built by markets. When the proletarian revolution occurs, if the entire economy is not already under a giant private monopoly, then inevitably, the material foundations to transform the economy into a fully planned economy would not exist, and you'd still have a large market sector. You can only establish economic planning to a scale proportional to your level of economic development which means the economy would not be fully planned.
This was something Marx, Engels, Lenin, and Stalin were all very well aware of. The Manifesto does not argue for the immediate abolition of all private property but a gradual abolition alongside economic development. Engels specifically says in The Principles of Communism that private property can only be abolished in proportion to the level of the development of the productive forces. Lenin argued in The Tax in Kind that immediate abolition of small producers would be economically impossible and suicidal. While Stalin went the furthest trying to fully plan the economy, he also admits in Economic Problems of Socialism in the USSR that he found such a task to be fundamentally impossible to achieve because of the low level of development of the USSR and that some markets had to remain.
Stalin had the additional idea of taking those market elements and transforming them into worker co-operatives in order to get rid of bourgeois ownership. However, there really is no theoretical basis for this in Marxism but just a strategy Stalin thought was useful in the USSR at the time.
Che Guevara wrote a good critique of this in his book Apuntes Críticos a la Economía Política where he criticizes the USSR's economic textbooks for conflating things the USSR did with socialism in general, that the USSR being the first socialist experiment often failed to separate between what was specific to the USSR's material conditions and what could be applied universally.
He goes onto criticize how there is no theoretical basis in Marxism for replacing all private ownership with co-ops and that co-ops do not constitute a form a socialist property, and in fact goes onto argue that workers in co-ops have fundamentally different class interests than workers in the public sector. The public sector workers benefit from an expansion of it, the co-op workers benefit from shrinking it, handing more power to the co-ops, accumulating more wealth individually, etc, etc.
He actually speculated the USSR might return to capitalism because they didn't take this problem seriously, that they assumed co-op workers had the same class interests as public-sector workers, and were not really concerned with what potential dangers they could present to constructing socialism. He also provides a couple examples where the co-op sector (the "kolkhozian class") conflicted with the public sector and the conflicts were resolved in favor of the kolkhozians, leading to deregulation and the restoration of buying and selling of means of production, something Stalin feared would end up laying the basis for the dismantling of the kolkhoz system in Economic Problems and potentially even the restoration of capitalism in the long-run.
Transforming the market sector fully into a co-operative sector was something the Soviets experimented due to the particularities of their material conditions, but it is nowhere to be found in Marxism and cannot be universalized to all countries nor is there any reason to, and the insistence that we have to embrace such as thing or else we're "revisionist" makes absolutely no sense and is just a dogmatic application of everything the Soviet Union did into other countries.
If we are not to be idealists that believe we can just wave a magic wand and instantly change our material conditions, then we would be forced to conclude that private property would continue to exist as a subordinated form of property for a long time post-revolution. If private property continues to exist, definitionally, so does the bourgeoisie. They would exist as a real material part of the economy and you have to work with that.
You can't just ignore your material basis and refuse to ever talk to the bourgeoisie because of an emotional visceral reaction against doing so. You can't pretend the economic base of your country isn't real because you don't like it. Even if you make them illegal, they will continue to exist in the form of black markets which plagued socialist countries which overly planned their economies in a way that was far too ahead of their productive forces.
Private property was recently legalized in Cuba very recently in the constitutional referendum and this was the same argument they had made as well. They made private property illegal, it sprung up as black markets anyways. These black markets flourished not because of evil people wanting to destroy socialism, but because the productive forces were underdeveloped and so the Cuban state was simply not economically efficient enough to plan the whole economy, and so many of these spontaneous black markets were providing real and genuinely useful services. We have seen in the DPRK for example a lot of black markets appear around food production due to food shortages where people grow and sell food independently of the central government that is not adequately providing enough on its own.
Simply crushing the small producers would thus only hurt their own economy, and making them illegal made it difficult for the state to regulate them. If a black market private business is actually providing a useful service, if they're illegal, the state would have to disperse them, and so they would be inclined to hide their activities, making it difficult for the state to regulate them.
By legalizing them, they no longer have a reason to hide their activities and it makes it easier for the state to regulate them, and thus control their development, and make sure the development of a non-state sector, which is inevitable from underdevelopment of the productive forces, would develop in a way beneficial towards the construction of socialism and not damaging towards it.
The only response to this ultraleftists give are visceral emotional reactions. They just hear "working with the bourgeoisie!!! evil!!!" and then get angry and upset about it because they think the only way to not be a "revisionist" is to just keep killing all private business owners until you have none left.
Yet, this was not what Marx nor Engels nor Lenin ever proposed. They all understood that markets have to develop alongside and supplementary to the development of planning, you can't just abolish one because you don't like it.
Stalin's economic model was specific to the Soviet Union's material conditions and the necessity to rapidly bring the country together and industrialize in order prepare for a fight against the Nazis. There is no reason to think Stalin's model should be universalized to every socialist country. But this is exactly what people are doing when they call China or Cuba or whatever revisionist for not making all private property illegal and turning all private businesses into co-ops.
And, again, if you don't make all private property illegal, you will inevitably have a bourgeoisie, and that means you'll inevitably at some point have to talk to them if you want to actually run an economy and not virtue signal. That doesn't mean the proletariat and the bourgeoisie share equal political power and footing, nor did the proletariat and peasantry share equal political power in that alliance, either. The country is still a dictatorship of the proletariat, but that doesn't mean the proletariat can't ever cooperate with other classes on any issue ever.