Because fear and conspiracy play no part in your daily relations with each other, you imagine that the same thing is true of your allies, and you fail to see that when you allow them to persuade you to make a mistaken decision and when you give way to your own feelings of compassion, you are being guilty of a kind of weakness that is dangerous to you and that will not make them love you any more. What you do not realize is that your empire is a tyranny exercised over subjects who do not like it and who are always plotting against you; you will not make them obey you by injuring your own interests in order to do them a favor; your leadership depends on superior strength and not on any goodwill of theirs.
Cleon, in Thucydides’ History of the Peloponnesian War