History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
and after we had once incurred the hatred of most of our allies, and several of them had already revolted and been reduced to subjection, and when you were no longer friendly as before but suspicious and at variance with us, it no longer seemed safe to risk relaxing our hold. For all seceders would have gone over to you.
And no man is to be blamed for making the most of his advantages when it is a question of the gravest dangers.
"At any rate you, Lacedaemonians, in the exercise of your leadership over the Peloponnesian states regulate their politiesl according to your own advantage; and if in the Persian war you had held out to the end in the hegemony and had become unpopular in its exercise, as we did, you would certainly have become not less obnoxious to the allies than we are, and would have been compelled either to rule them with a strong hand or yourselves to risk losing the hegemony.
Thus there is nothing remarkable or inconsistent with human nature in what we also have done,just because we accepted an empire when it was offered us, and then, yielding to the strongest motives—honour, fear, and self-interest—declined to give it up. Nor, again, are we the first who have entered upon such a course, but it has ever been an established rule that the weaker is kept down by the stronger. And at the same time we thought we were worthy to rule, and used to be so regarded by you also, until you fell to calculating what your interests were and resorted as you do now, to the plea of justice—which no one, when opportunity offered of securing something by main strength, ever yet put before force and abstained from taking advantage.