Classical Greek civilization was the high point of the 'city-state', but the poleis could only survive if there was no strong nation-state messing around with t

Classical Greek civilization was the high point of the 'city-state', but the poleis could only survive if there was no strong nation-state messing around with them. They rallied together to prevent Persia moving Westwards, but simply could not get their act together to stop an old-fashioned imperial kingdom, Macedonia. And once the Romans expanded, they had no hope of regaining autonomy.