George Orwell's Animal Farm suggests that man cannot, in fact, achieve a utopian society, as the protagonists in the story turn their backs on their ideals. It's important to remember that the book was intended to be an allegory for the Soviet Union under Josef Stalin. Stalin's attempts to remake society in the USSR had aroused great interest among intellectuals around the world, but the terrible human costs, including his ruthless purges, became apparent, many of these intellectuals became greatly disillusioned. (Significantly, publication of the book, which was written in 1939, was delayed until after 1945, when the USSR and Great Britain were no longer wartime allies.)
We see many of the elements of Stalinist government in Animal Farm, including a power struggle between Napoleon and Snowball, grinding labor to achieve animal self-sufficiency on the farm, a bloody purge orchestrated by Napoleon, the development of a privileged group of "apparatchiks" in the form of the pigs, and of course, Napoleon's ascent to absolute power. The well-intentioned attempt by Old Major to establish a utopia on the farm descends into a nightmarish dictatorship due to the ambitions of the pigs and the gullibility of some of the other animals.