Man is by nature, a territorial creature this in order to give his descendants the conditions to survive.
He needs the land to provide him all he needs to live. This is why throughout all history we had wars.
I don't think we can change our genes so easily to be able to choose not to fight...
As a specific tribe (like jews) we can loose some of our men in a battle but we gain the opprtunity to give life for the rest.
We can see this also in the plant kingdom.
A buch of Anabasis articulata will "kill" parts of itself in a drought season to be able to grow again later....
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"C'est la vie !", this is my opinion although I hate to think about it.
Intersting.
I think we are in the midst of a change, human nature is being transformed, and within 10 years we will see the impact.
Will it be flowers or thorns? Time will tell.