Imagine for a moment that time travel is real. A time traveler decides to go back into the major eras of human history, he first goes back to the 30s to see Hitler in person, then he watches on a balcony as the french revolution sweeps through paris, he goes back to medieval times to check out what england might have been like, he goes to witness the fall of rome, and then he decides to go observe the unfolding of the iron and bronze ages. Finally he has decided :
He goes back to the stone age, over 3 million years ago and sees a man. He takes this man with him in his time machine to the current day. A man who has not gone through the steps of evolution our time traveler has, this stone age man, who is likely violent, and had to be for his bloodline to survive, how would he adapt in 2025? Could he adapt in 2025? Would it be possible at all?
That's exactly what we're doing with blacks. We are taking people who skipped over 3 million years of civilizational advancement, who never evolved beyond the stone age, and sticking them in 2025. And most normies see absolutely no problem with this and expect it to not lead to chaos and disaster.
In other words, the Africans would have invented skyscrapers had "somebody" (jews) not dragged them onto boats and brought them to the West; the Aztecs would have discovered flight had it not been for the Spanish interrupting their baby sacrifices; and the Chinese would have invented the computer had it not been for the British and their opium, etc. Diamond's whole thesis argues that the state of Humanity globally would have been better today had them White devils not been so selfish and destructive of other cultures' natural developments.
In a roundabout way, he'd have to agree that niggers all be sent back to pick up where they left off in their "development."