Bro, I wrote you a long reply but it didn't take, I guess. The gist was, I agree with you that multiple races inside the same society weaken it, and humans are inherently tribalistic.
However, I posit that:
Tribes can be oriented around more than just superficial appearance. Factors such as religion (Islam, Christianity), prolonged shared geography (Mexican natives and Spaniards), overwhelming force (the conversion of distinct African ethnic groups into the artificial "Black" category) etc have historically eliminated ethnic groups by combining them with others.
Humans naturally want to blend, typically only artificial political incentives prevent it (Spanish caste systems, anti-miscegenation laws, subversive Cultural Marxist Buzzfeed articles about fighting whiteness by not dating whites)
In the West, race is a system, a system created in order to treat people differently. Slave sellers and their customers needed to explain why it was okay for Christians to keep slaves, and a hasty categorization based on appearance was the birth of "Black". It was invented out of necessity from incentive. Today, the incentive for "Black" persists with everyone from the known race hustlers and authors to college sophomore girls who need a cause to belong to benefiting from its existence. The other distinct racial categories have their own reasons for existing. When the incentive for a concept in a culture to exist disappears, it disappears.
There's more to it, and this isn't as good as what I first wrote lol. I respectfully disagree and I am sure you are not convinced, but please try to see things as I do from my position.
Diversity is supposed to be the basis for a stronger consolidation.
Don't incentivize people to prioritize their ethnic affiliations over their civic ones and not assimilate
Don't incentivize the native population to not criticize the new population or appropriate useful parts of it.
Don't take foreigners that have no chance in hell of doing number 1.
The only demographic data used for legal purposes shall be as follows: A. Citizen B. Lawful Resident 3. Going back where they came from
Guys I did it I succeeded in the balancing act of not being Nazi Germany and not being Somalia.
Bro, I wrote you a long reply but it didn't take, I guess. The gist was, I agree with you that multiple races inside the same society weaken it, and humans are inherently tribalistic.
However, I posit that:
Tribes can be oriented around more than just superficial appearance. Factors such as religion (Islam, Christianity), prolonged shared geography (Mexican natives and Spaniards), overwhelming force (the conversion of distinct African ethnic groups into the artificial "Black" category) etc have historically eliminated ethnic groups by combining them with others.
Humans naturally want to blend, typically only artificial political incentives prevent it (Spanish caste systems, anti-miscegenation laws, subversive Cultural Marxist Buzzfeed articles about fighting whiteness by not dating whites)
In the West, race is a system, a system created in order to treat people differently. Slave sellers and their customers needed to explain why it was okay for Christians to keep slaves, and a hasty categorization based on appearance was the birth of "Black". It was invented out of necessity from incentive. Today, the incentive for "Black" persists with everyone from the known race hustlers and authors to college sophomore girls who need a cause to belong to benefiting from its existence. The other distinct racial categories have their own reasons for existing. When the incentive for a concept in a culture to exist disappears, it disappears.
There's more to it, and this isn't as good as what I first wrote lol. I respectfully disagree and I am sure you are not convinced, but please try to see things as I do from my position.