@CalamityJane,
Italian highways used to be anarchic but glad to report I’ve noticed an improvement in Italian driving styles over the years. One can now use a pedestrian crossing without being driven over, for instance. I guess Europe does have a normative effect. E.g. Italian people traveled around The continent and realized they don’t necessarily need to behave like assholes every time they are behind the wheel...
This said, I personally learned to drive in Peshawar, North-West Frontier, Pakistan. The only word to describe traffic there is “chaotic”. The basic rule is: the larger vehicle has priority, because it can smash the smaller one. A variety of drought animals (buffaloes, camel, donkeys, horses...) complexifies traffic further as they all have their own behavior, speed, etc. Roman traffic seems quite tame in comparison.