Why couldn't humans have evolved during the last 10,000 years?

They could, but not much. Evolutionary psychologists downplay the possibility of significant cognitive evolution in the 10,000 or so years since the advent of agriculture (a period of time known as the Holocene) for reasons of both science and political correctness. Scientifically, 10,000 years (500 generations) is not much time for natural selection to act, and it certainly is not enough time to evolve new, complex adaptationssophisticated mechanisms coded for by numerous genes.

It is possible, however, that humans could have evolved minor cognitive adaptations during the Holocene. Just as some populations whose subsistence relied on herds of domesticated animals evolved to digest lactose as adults, populations could have evolved simple cognitive adaptations that their hunter-gatherer ancestors did not possess. For this to occur, there would have had to have been environmental conditions that were (1) new, (2) constant over most of the Holocene, (3) relevant to reproduction, and (4) ... more.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.