A Deepness of Thought
One of the greatest demographic shifts in world history was the virtually elimination of Native Americas by Western Europeans. It's difficult to admit that our fore bearers took the land we now inhabit by genocide. But the horror of it is not unique to history. What is unique is the scale. The most popular theory now is that plagues brought from Europe decimated the Native Americans and there is much evidence to support this. Another theory proposed in Guns, Germs and Steel, is that domestic animals gave the Europeans a great advantage. Cows and horses increase productivity in Europe to the point that large numbers of people could escape subsistence farming and pursue technological advancement. One theory I have not heard discussed much is writing. Or more specifically writing with an alphabet, or even more specially, writing with vowels.
Writing developed independently a few times in world history. But writing with a phonetic alphabet only developed once, in the Middle East and writing with vowels only developed once, in Greece. There are two great advantages to this system of writing; it is relatively easy to learn, and it can be used to communicate abstract ideas.
Technological achievement is useless unless you have a way to pass it on.
We Europeans may have lucked out with the development of the alphabet but what we did with it was up to us. The alphabet enabled the development of powerful technology but it also gave us the ability to communicate the ethics of what we did with it. Unlike the plague theory, if the alphabet enabled the Europeans to wipe out the Native Americans, then the responsibility is all ours.