As Sir Acton says, "Absolute power is absolutely corrupt" (1887). Looking back on history, you can see that the leader tends to change after grasping power. What they need is just a few sparks that light up some bad things. There are minor changes, please make a minor change. Napoleon changed rules one by one to fit him and the needs of the squirrel at George Orwell's farm and eventually destroyed them. Napoleon and Squealer show that power violates leaders through their actions and attitudes towards society, and through efforts to improve livestock.
In order to get this theme, he replaced humans with allegorical animals and showed the process of power destruction. On an animal farm, the revolution began with one of the oldest pigs. Old occupational dream is how humans use these animals. Animals are great for running their farms. He said: "This is not such a clear comrades: all the sins of our lives are released from human tyranny and can only remove human beings, our labor product is our own Thing.
Animal farms are also about how power, power can erode our best people. Before Napoleon took power, he was a sincere leader and seemed to want the best animal and animal farm, but few will come after he gradually gained more and more power. First, Napoleon looked down on humans and told other animals that "human beings serve the interests of every living creature other than their own." The situation has changed after he grabbed power. Animals are richer people - of course, except for pigs and dogs. And eventually, Napoleon completed the change he despised: