Machiavelli, when writing to the Prince of Florence, once said that the purpose of politics is 'acquisition and maintenance'. A perfect example of this comes in the Speech of the Corinthians (1.69). When speaking of the growing Athenian aggression, the Corinthians accuse the Spartans of allowing the Athenians to gain the power that they've come to gain.
" For all this you are responsible. You it was who first allowed them to
fortify their city... you, Spartans, of all the Hellenes are alone inactive,
and defend yourselves by not doing anything but acting as though you
would do something; you alone wait until the power of an enemy
is becoming twice it's original size, instead of crushing it in it's infancy"
(Thucydides p. 39)
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