Animalism can be seen as a satire on the ideology of Soviet Communism. The similarities between the two are not very hard to spot. Animalism is a collectivist creed that promotes the solidarity of the poor and the downtrodden against a common enemy. In the case of Communism, this means the bourgeoisie; with Animalism, it's the drunken farmer Mr. Jones.
Animalism aims to instill the long-suffering farm animals with a sense of pride in their identity. There are clear parallels here with Communism, which accords the proletariat a world-historical role in abolishing capitalism. Both ideologies hold out a positive, inspiring vision, a future in which hunger, want, and repression are a thing of the past.
Yet Animalism, like the Communist ideology it so ably satirizes, ultimately leads to chronic shortages, economic failure, and brutal repression. Though Old Major's ideas were supposed to lead the animals to the Promised Land, in the hands—or rather, trotters—of Napoleon and his gang of pigs, they've brought immense suffering and bloodshed to the farm.
Napoleon, like the Soviet dictator Stalin on whom he's based, has brought out the authoritarian implications of the reigning ideology and established himself as a dictator, ruthlessly destroying anyone who gets in his way. Under his despotic regime, everyone is expected to do as they're told: to act the same way and to think the same way. And woe betide anyone who dares to step out of line.
As well as being repressive, Animalism is also chronically inefficient, just like Communism. There are constant shortages on the farm, and yet Napoleon still insists on selling food to local towns and farms. In turn, this leads to starvation, an allusion to the appalling man-made famines that Stalin inflicted upon the Soviet Union during his industrialization drive in the early 1930s.