Yet another brain dump of the real reasons for current (and future) foreign policy:
“When some prince or people broke away from obedience to a ruler, they were immediately accorded the title of ally of the Roman people. This way the Romans made them sacred and inviolable, so that there was no king, however great, who could be sure of his subjects or even of his family for a moment.
When they allowed a city to remain free, they immediately caused two factions to arise within it. One upheld local laws and liberty, the other maintained that there was no law except the will of the Romans. And since the latter faction was always the stronger, it is easy to see that such freedom was only a name.
Finally, they judged kings for their personal faults and crimes. They heard the complaints of all those who had some dispute with Philip; they sent deputies to provide for their safety. And they had Perseus accused before them for some murders and quarrels with citizens of allied cities.
When disputes broke out in some state, the Romans adjudicated the matter immediately, and by this means they were sure of having against them only the party they had condemned. If princes of the same blood were disputing the crown, the Romans sometimes declared them both kings. If one of them was under age, they decided in his favor and took him under their tutelage, as protectors of the world. For they had carried things to the point where peoples and kings were their subjects without knowing precisely by what title, the rule being that it was enough to have heard of them to owe them submission.”
Montesquieu, Considerations on the Causes of the Greatness of the Romans and their Decline, 1734 (CHAPTER VI. THE CONDUCT THE ROMANS PURSUED TO SUBJUGATE ALL PEOPLES)