For the true author of the subjugation of a people is not so much the immediate agent, as the power which permits it having the means to prevent it. - Thucydides

(Peloponnesian Generals:) The skill (ἐπιστήμη) of your enemies which you so greatly dread, if united with courage (ἀνδρείαν), may be able in the moment of danger to remember and execute the lesson which it has learned, but without courage (εὐψυχίας) no skill (τέχνη) can do anything at such a time.

τῶνδε δὲ ἡ ἐπιστήμη, ἣν μάλιστα φοβεῖσθε, ἀνδρείαν μὲν ἔχουσα καὶ μνήμην ἕξει ἐν τῷ δεινῷ ἐπιτελεῖν ἃ ἔμαθεν, ἄνευ δὲ εὐψυχίας οὐδεμία τέχνη πρὸς τοὺς κινδύνους ἰσχύει.

For fear makes men forget, and skill which cannot fight (ἀλκῆς) is useless.

φόβος γὰρ μνήμην ἐκπλήσσει, τέχνη δὲ ἄνευ ἀλκῆς οὐδὲν ὠφελεῖ.

(Book 2 Chapter 87.4)

You should punish in the same manner those who commit crimes with those who accuse falsely.

The causes which led to the defections of the allies were of different kinds, the principal being their neglect to pay the tribute or to furnish ships, and, in some cases, failure of military service. For the Athenians were exacting and oppressive, using coercive measures towards men who were neither willing nor accustomed to work hard.

And for various reasons they soon began to prove less agreeable leaders than at first. They no longer fought upon an equality with the rest of the confederates, and they had no difficulty in reducing them when they revolted.

Now the allies brought all this upon themselves; for the majority of them disliked military service and absence from home, and so they agreed to contribute their share of the expense instead of ships. Whereby the Athenian navy was proportionally increased, while they themselves were always untrained and unprepared for war when they revolted.

(Book 1 Chapter 99)