Well apart from the bit about the allies during the 2nd Punic war you don't seem to have replied to anything my post at all. Anyway during the war quite a few subjegated peoples and allies defected to Hannibal, these include major ones such as Capua (along with most of the Campanians), Syracuse (causing other greek cities in sicilly to revolt as well), the Samnites, the Lucanians, Tarentum and the Bruttians as well as various other cities such as Thurii, Croton and Heraclea among others. While this did in no way represent the majority of their allies it ws still a significant chunk and certainly disproves your rather flippant remark that "History has proved that not even Hannibal could make an ally of Rome turn on them."
Now if Alexander had invaded after his conquests in the east he could rely on the support of most if not all of the Greek cities in the area at the very least, Rome's list of allies on the other hand is much smaller, they have a powerful one in the form of Carthage but apart from that they could only expect support from the Latins and the Campanians. The neighbouring Samnites and what was left of the Etruscans would at best remain neutral and at worst join the invaders (quite likely with the Samnites considering they were warring with Rome at the time), the other Italian peoples would probably keep to themselves.
I do find your belief that the Romans of the time were some kind of super people superior to everyone else in martial and political skill rather odd.
The truth of the matter is that
at the time they were a small somewhat unremarkable republic that showed the occasional flash of the greatness they would eventually achieve but
at the time that future was in no way certain.
This is the last I shall say on the matter.

Bookmarks