A longtime favorite of ours, George Orwell's Animal Farm speaks very clearly about the nature of human behavior and its relationship to power. Orwell created it as an allegorical satire of the Soviet Union's devolution from a democratic socialist system to a brutal dictatorship. Although the book speaks specifically about the changes of power in Russia after the Bolshevik Revolution, its theme is universal, and just as relevant today as ever.
Revolution and regime change can lead those newly in power to begin to bend the rules to their benefit without the consent or full understanding of the general population. Orwell referred to this as a "change of masters," as illustrated by the pigs in Animal Farm. As the pigs become more and more like the humans they overthrew, they adjust laws to satisfy their needs--keeping the best food for themselves, allowing themselves to drink alcohol, and so on. It’s a recurring theme in world history: the ruling class creating a system that benefits them in every way while excluding the people they claim to represent.
Animal Farm illustrates how easily this kind of self-dealing can come to dominate a political system and erode ideals of equality. It's a form of creeping oppression that's made an alarming comeback around the world over the last few years, even in our own country.