The Roman historian Livy, in a celebrated passage, [footnote: Titi Livi, ab Urbe Condita, Liber IX, caps. xvii-xix.] has speculated upon what would have happened if, in the fourth century B.C., Alexander the Great had turned his arms against the Roman Commonwealth. On this distinguished precedent we may venture to put an imaginary question of our own. What would have been the course of history if the career of Alexander the Great and the career of his father Philip had been ruled out a priori by the previous incorporation of Macedonia into a vast Chalcidian Commonwealth of city-states? In that event might not Hannibal, on the morrow of Cannae, have found himself able to summon to his aid a politically united Greece which would have been a power of the same calibre as Roman Italy? And in the face of such overwhelming odds as these, could Rome have avoided the fate which actually overtook Olynthus in 348 and Macedon in 168 and Carthage in 146 B.C.?
The Livian speculation was the subject of a BBC radio programme in 2003 which you can listen to here. The Chalcidian city of Olynthus fell to Philip of Macedon in 348. The other two dates refer to Roman victories.
A Study of History, Vol III, OUP, 1934