Lighter Skin = Better?

[Anomalocaris]

Rome had plenty of competitors, Rome was sacked by rival civilizations and Rome didn't have as much territory as Britain, neither did the Egyptians so which empires are you talking about which had no rivals and always faced down peer competitors.

Yeah, and England was invaded by the French.

The point is from 200 BC to around 250 AD, the core of Roman state was almost continuously secure from even the threat of foreign aggression, all peer power that could strategically threaten security and economic well being of Rome has been overran and extinguished. The only threat to core of roman state was from civil war.

Egypt's core was also secure majority of the time from foreign invasion during its first 2000 years.

In the history of most long lasting empires, there would be interregum periods of disruptions and civil war when even its normal secure core could be vulnerable to invasion. This happened several times in Egyptian history, and to Rome between 250AD - 400 AD. But during the heights of their power, they were not just secure because they played off their rivals against each other. They were secure because they've subjugated all their potential rivals that could threaten their core.

This Britain never did.


BTW, Hong Kong wasn't always right next to China. Most of China south of Shanghai were "acquired" in the course of Chinese expansion. The first unified Chinese state was maybe 25% of China's current size.