Oppressing people is expensive and dangerous. It takes huge police and military forces, which costs a lot! Such force, in turn, also means the risk of being overthrown. Better for oppressors to come up with a system in which the oppressed police themselves and their neighbors. It’s cheaper and much less volatile. But how do they get people to work against their own interests? Sadly, history has proven it’s simpler and more common than you’d might think.
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