Actually, Khan was clearly a not-very-Indian man of Spanish background rather than "vaguely Spanish."
All they really have to do is say "several centuries ago" and leave it at that.
I assume they'll stick with TWOK's "genetic engineering" retcon rather than returning to "Space Seed's" selective breeding explanation.
That argument doesn't really hold water. I have a parent who is 100% Slavic while the other parent is a mish mash of European and English ethnicities. My siblings and I closely resemble the mish mash parent. My neice has a parent who is 100% Hispanic (Mexican) and except for the brown, not black hair, she looks much like her mish mash parent. The same can be said about my spouse's parents, one being 100% Nordic and the other mish mash. All the siblings closely resemble the parent who has many ethnicities involved in their genetics.
KNS used the phrase "genetic engineering" in
TWOK to describe his superiority (supremacy) over all others
. Spock used the phrase "selective breeding" in
Space Seed as an attempt to improve the race
, while Kirk addressed the issue of his not being a "product of controlled genetics" with a red (not gold) shirted KNS. Any which way you say it, it amounts to the same thing.
The mid 1990's was a time referrence given to the "last Great War," of which McCoy then replied as "the Eugenics War." While there was no reference to the
Botany Bay, that class of ships was last built in the 1990's.
Is this Khan? If I were basing my guess on the fact that the first actors sought after for the role of the villian were Hispanic, I guess I might assume that it's KNS, but you know what they say about assume. He could simply be an augmented human that uses the title of Khan. Hopefully, we'll find out next month.
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At the time this script was written, most of the Western cultures had been involved with or reading about Eugenics and the idea that some races were superior to others, and some races quite inferior to most. I'm sure this only aggravated the lesser thought of races, and hindered foreign policy greatly. Efforts were made (through abortion) to create a better breed of people. Why use the Sikh ethnicity? McGivers said they were a race of fantastic warriors. This is a requirement in war and ruling a population. Why Mexican? The Aztecs and Mayans of the Latin American countries are thought to be some of the most intelligent ethnicities in history.
Roddenberry liked to send messages through his episode, of what he though about current world affairs of the time. My impression of the episode was that it meant to say that selective breeding through the use of manipulated genetics is a fool's folly.