Thucydides 2. 63

Then it is right and proper for you to support the imperial dignity of Athens. This is something in which you all take pride, and you cannot continue to enjoy the privileges unless you also shoulder the burdens of empire. And do not imagine that what we are fighting for is simply the question of freedom or slavery: there is also involved the loss of our empire and the dangers arising from the hatred which we have incurred in administering it. Nor is it any longer possible for you to give up this empire, though there may be some people who in a mood of sudden panic and in a spirit of political apathy actually think that this would be a fine and noble thing to do.

Your empire is now like a tyranny: it may have been wrong to take it; it is certainly dangerous to let it go.

 And the kind of people who talk of doing so and persuade others to adopt their point of view would very soon bring a state to ruin, and would still do so even if they lived by themselves in isolation. For those who are politically apathetic can only survive if they are supported by people who are capable of taking action. They are quite valueless in a polis which controls an empire, though they would be safe slaves in a polis that was controlled by others.