Conflicts over land ownership didn't start until the Reconquista just before the modern era. Prior to that the idea that people privately could own land didn't exist. This idea was very helpful for colonization and it is not natural.
Kwakigra
The bit at the end starting with agriculture is much smaller relative to human history. Homo Sapiens attained our present taxonomy about 350,000-500,000 years ago. Agriculture, armies, and empires as we now know them all started around 10,000 years ago.
There are some cogent points in there, but the author fails to realize that the problem with capitalism is the capitalists themselves. The issues they complain about are the inevitable consequence of allowing capitalists to own the means of production rather than the people. Capitalists care less about being patriotic and doing good deeds than they do about their capital holdings, and an investment in corruption and cronyism is one of the safest bets capitalists with sufficient power can make.
Living paycheck to paycheck in the US often means working over full time hours across a few part time jobs and still not always being able to pay all the bills every month. No one should be ok being a wage slave no matter where they live in the world.
We're not talking about the use of violence generally, which is a nuanced and vastly complex topic. We are talking about literally wiping out 37% of humanity, which is much less nuanced or complex. Such ideas should have been left behind during the previous century.
What would the mechanism be to exterminate 37% of the human race with this degree of precision? Who would be in charge of it and why do we trust them not to continue using such a tool? If it's not a military operation, what would it be?
A major, fundamental issue with your suggestion is that it assumes there are multiple species of humans which exist who are fundamentally different on a genetic level. If I was a god who could snap my fingers and instantly obliterate all conservatives, it would not be the end of conservatism. You yourself are locked in violent thinking, are you absolutely certain that your own children couldn't possibly be attracted to violence when you yourself believe that mass violence on an unprecedented scale is the best opportunity to create a just world? Are you certain that no child born of any survivors would carry any temptation to take advantage of others as those in the past have? Are you sure no one in the surviving billions of people, generationally removed from your mass killing, would have the ability to re-invent a dipshit philosophy like fascism? I don't think its bad genes which causes the myriad evils which result from trauma and poverty. As long as there is an incentive for people to behave in anti-social ways, people will behave in anti-social ways.
You are correct that unreasonable people can't be reasoned with. Dogs also can't be reasoned with but are not a threat to society. This is because we manage them. Trump has demonstrated that you can be a fool-whisperer like Cesar Milan is a dog-whisperer. The problem is that he uses his ability to influence fools for evil instead of good. These unreasonable fear-motivated dupes can be dealt with in ways that take advantage of their cowardice to neutralize themselves as a threat or depend on pro-social groups rather than use their cowardice to fuel despotism. The human race of which you and I are part will contain a vast array of people acting and being acted upon. We as a species can be influenced, but eugenic movements to root out undesirables have never worked.
I have never heard an anarchist speak this way. I don't want to be left alone, I simply don't want a class of people who believe they hold authority over me as my superiors. Anarchists shouldn't be using anyone. A stable anarchy can't exist as long as people are still thinking in terms of using each other as resources for their own interests.
Murdering each other is against our nature but we've been doing it prolifically since the advent of agriculture so much so that war is seen as a "natural" part of life. The solution of killing all the bad guys so only good guys are left has probably been on the mind of most of those soldiers and military leader for the last 10,000 years. It turns out this approach doesn't end authoritarianism or violence.
If somehow we killed 37% of the human population in no way would that bring us closer to a fair and equitable world. It would be exactly in line with dominator culture hegemony which has existed for the most recent few thousand years. What you described would not be revolutionary, but typical for the present buccaneer philosophy which is popular among the powerful and their thralls.
In the original Star Wars, the Empire was based on the American empire and the rebellion was based on the Vietcong according to George Lucas.
There is a major difference between conquering people and claiming the places they reside as part of empire versus drawing lines on a map and claiming to legally own the land itself.
When the Romans were conquering their empire in Europe, they weren't claiming land and claiming that those who resided on that land were now subject to the Roman Empire. This is however literally what Spain did during the Reconquista and what the conquistadors did in the Americas afterward. It's also how these thigs tend to go today.
The Romans, like the Aztecs, conquered groups of people and forced them to be subjects. The land they were on was less important than the people themselves being subjugated to the hegemon. If a subject city's population decided to abandon it and establish their city elsewhere within Rome's martial reach, the Romans would keep the people rather than the useless unoccupied land.
Feudal estates and fiefdoms are a kind of proto land ownership but even this was distinct to how we would consider it today. Claims were much more vague and impossible to enforce without the cartography tools we have now. Again, they were claiming ownership of the nation as a people, not a nation defined by borders and acreage.
Of course there was plenty of disagreement as to which hegemon runs which settlement. The disagreement was not that two governments had a legal claim to the same piece of defined land, but things like "God chose me to rule whatever I can reach, and I can reach you" or simply "I can beat you in war, so these people are mine."
People "owned" their homes and used whatever land around it to farm, but not as in they had a legal claim to the whole piece of property and a franchise to do with that landed property as they pleased. They owned it because they resided there and could keep up what they were using. Wealthier people had more people to manage more territory in their behalf, but even this was more about the subjects than the land they lived on, which was understood to be incidental compared to how we would see it today. Unoccupied, unused land miles away from where anyone lived was not being fought over. Wherever they lived domination of people was fought for.