History of the Peloponnesian War

"And of all this you are yourselves the authors, in that you suffered them upon the end of the Persian war to fortify their city and again afterwards to raise their long walls, whereby you have hitherto deprived of their liberty not only the states by them already subdued but also your own confederates. For not he that bringeth into slavery, but he that being able to hinder it neglects the same is most truly said to do it, especially if they assume the honour to be esteemed the deliverers of Greece [as you do].