I'm not so sure it's "genetic," this propensity for violence among so-called "white" people. I tend toward the geographic and climatic answers. As you put it, the "harsh European climate" over thousands, if not millions, of years produced a people who were of necessity forced by “nature” itself to "compete," scramble, and fight for just about every scrap of food, for warmth, for everything that sustains life. That's why they worship the "individual" rather than the "collective" or the "society" as a whole.

Most of the rest of the world did not have to engage in such wholesale and never-ending violence simply to subsist, to survive, to live. Oh, sure...in Africa there were ritualized tribal wars long before the white folks showed up. But most of these “conflicts” and “wars” amounted to blustering shouting matches and threat-displays. Rarely did anybody actually die. The idea, the point, the objective, was humiliation, embarrassment — not killing the opponent. (It’s here where African slavery enters. The “defeated,” the humiliated, the embarassed, the “conquered” were often reduced to just not “prisoners of war,” but to “slaves”— a slavery, unlike the Euro-American iteration, that left the humanity of the enslaved intact.)

Same with many "Indian" tribes here in the Americas (save the Caribs) of the Bahamas --until Columbus showed up. True, the Aztecs, Mayans, and Incas had their bloody periods....but nothing like the mass genocides which regularly, like clockwork, went down forever on and across the backwater Eurasian subcontinent, a/k/a Europe.

One of my favorite examples of an evolution-based propensity for violence among white people (i.e., Europeans and their North American and Australian cousins) is this: The Chinese invented gunpowder, right. They used it for thousands of years for celebrations, rituals, fireworks, and ceremonies.

We know only too well what happened, right, when the Caucasians got their hands on gunpowder.

Interesting essay.