The author's statement that "European colonists shot, displaced, or infected many of them, and the survivors interbred with Europeans" is a bit dissonant. And, the complete absence of Islamic, Arab slave traders is suspect as well. I suppose he's lumped them under "white" to avoid muddying his false dichotomy.
Well, what happened to the Khoisians is essentially true as described by Diamond.
And Arabs are considered as Caucasians..essentially "white"...by virtually all scientists.
For emotional reasons I see a lot of people on FR that desperately want Arabs to be a different race but it just doesn't hold water. If Bin Laden's or Saddam's unidentified bones were found in Central Park the news would be reporting the unidentified body of a Caucasian was found in Central Park.