History of the Peloponnesian War

And let not any man conceive that you shall herein at your own danger defend the territory of another. For though Lesbos seem remote, the profit of it will be near you. For the war will not be, as a man would think, in Attica but there from whence cometh the profit to Attica.

This profit is the revenue they have from the confederates, which, if they subdue us, will still be greater. For neither will any other revolt; and all that is ours will accrue unto them, and we shall be worse handled besides than those that were under them before.