I am the same as I was, and do not alter; it is you who have changed. What has happened is this: you took my advice when you were still untouched by … - Thucydides

it is not so much your hostility that injures us; it is rather the case that, if we were on friendly terms with you, our subjects would regard that as a sign of weakness in us, whereas your hatred is evidence of our power.

Our opinion of the gods and our knowledge of men lead us to conclude that it is a general and necessary law of nature to rule whatever one can. This is not a law that we made ourselves, nor were we the first to act upon it when it was made. We found it already in existence, and we shall leave it to exist for ever among those who come after us. We are merely acting in accordance with it, and we know that you or anybody else with the same power as ours would be acting in precisely the same way.
Goodwill shown by the party that is asking for help does not mean security for the prospective ally. What is looked for is a positive preponderance of power in action.

Hatred also is short lived; but that which makes the splendor of the present and the glory of the future remains forever unforgotten