I suppose part of the problem in this discussion is I don't understand where you are coming from in regards to anarchism and communism being two competing models. I don't get that. Anarchism is a political system. Communism is an economic system. The two aren't competing. There are anarcho-capitalists, there are parliamentary-communists, and so on. In Barcelona, the anarchists ran the city and surrounding countryside using communism as the economic model.
You still seem to be implying that anarcho-communism is not valid because all attempts at implementing it have "ended in failure" without recognizing that the failure in Barcelona had nothing to do with the implementation but was due to other factors. Thus my use of the farm analogy.
We do agree that it is an unproven model, at least in part. But that can't be stretched to claim that it must fail. The most that can be said, using real-world evidence as the only standard, is that anarcho-communism might or might not work and that when it was tried, that one time, it was overrun by outside forces. Whereas, democratic free market capitalism has been proven to be a failure
in implementation time and again for several centuries , requiring large infusions of socialist theory in order to make it palatable and for it to function in the real world. So, my stance is that of the two, anarcho-communism has not been proven to be a failure while democratic capitalism has failed.
But again, I fully recognize that anarchism and communism are essentially utopian because they haven't been tried on a large scale or long term. Let's not get into an argument about Marxist-Leninism and Stalinism being communism, though. They bear more resemblance to a centrally-controlled capitalism than to communism. The argument against trying to mix a centralized totalitarian political system with communism got Mikhail Bakunin kicked out of the First Communist International by Marx. I side with Bakunin. For communism to work it must be deeply rooted in democratic ideals, especially individual freedoms and as weak a central government as possible - thus the mixture of communism with an anarchist political leaning.
I also feel that free market capitalism has been proven to be utopian and unrealistic since it has never been implemented without ending up strongly mixed with socialist theory. So, of the two, it seems to me to be more sensible to choose the system which hasn't been proven to be unviable in the modern world; and that would be anarchism and socialism/communism, which is otherwise known as anarcho-communism or anarcho-sydicalism or libertarian socialism, and so on.
While we wait for our utopian dreams to manifest, you and I can at least agree that in the meantime a middle ground seems to work best. Our only argument being how far along the scale from one end to the other to place the marker.

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