Funeral Oration

Then the Athenians, in anger, advised them, if they meant to be of this mind, to encompass the whole Peloponnese with a wall: for if they themselves, betrayed by the Greeks, should be united with the barbarians, these on their part would have no need of a thousand ships, nor would the wall at the Isthmus help its builders, since the empire of the sea would belong without hazard to the King.