Rough Roman Memes

In support of your point, here's a nice little quote from Emperor Claudius, who was also a scholar and a historian:

What was the ruin of Sparta and Athens, but this, that mighty as they were in war, they spurned from them as aliens those whom they had conquered? Our founder Romulus, on the other hand, was so wise that he fought as enemies and then hailed as fellow-citizens several nations on the very same day. Strangers have reigned over us. That freedmen’s sons should be intrusted with public offices is not, as many wrongly think, a sudden innovation, but was a common practice in the old commonwealth. But, it will be said, we have fought with the Senones. I suppose then that the Volsci and Aequi never stood in array against us. Our city was taken by the Gauls. Well, we also gave hostages to the Etruscans, and passed under the yoke of the Samnites. On the whole, if you review all our wars, never has one been finished in a shorter time than that with the Gauls. Thenceforth they have preserved an unbroken and loyal peace. United as they now are with us by manners, education, and intermarriage, let them bring us their gold and their wealth rather than enjoy it in isolation. Everything, Senators, which we now hold to be of the highest antiquity, was once new. Plebeian magistrates came after patrician; Latin magistrates after plebeian; magistrates of other Italian peoples after Latin. This practice too will establish itself, and what we are this day justifying by precedents, will be itself a precedent.

I have a fantastic book on the subject, Imperial Ideology and Provincial Loyalty in the Roman Empire, highly recommend.