The Prince by Machiavelli

This is one of the most misread books of all time. If you read it carefully, you’ll see that he does not argue for winning at any cost. Instead, Machiavelli carefully weaves a more nuanced argument: that if your ends are just and good, then the means to achieve them might sometimes be ugly.

That is to say, he’s not saying it’s okay to be a jerk, but rather to be willing to do what you must to reach just ends.