Warfare has no adaptive value
(see Table below)

The bizarre idea that warfare is adaptive. In the First World War, millions of men did not pass their genes along. 

Millions of men submitted to their countries at the behest of the leaders of their nations: a profoundly SPIRITUAL (irrational) endeavor: love of country; a form of religious belief. 

Convoluted theories (I am aware of them) function in the name of maintaining the fantasy of "rationality." If something happened, it must have had adaptive value. Denial of human irrationality. Incorrect application of Darwin's theory of natural selection.

Where is the principle of parsimony? Where is Occam's razor? 

December 11, 1914, a French soldier to his parents:

If this letter comes into your hands it will be because I am no more and because I shall have died the most glorious of deaths. Do not bewail me too much; my end is the most to be desired. Speak of me from time to time as of one of those men who have given their blood that France may live and who has died gladly.

P. H. Pearse, founder of the Irish Revolutionary movement—was thrilled to observe the carnage of the First World War:

The last sixteen months have been the most glorious in the history of Europe. Heroism has come back to the earth. It is good for the world to be warmed with the red wine of the battlefield. Such august homage was never before offered to God as this—the homage of millions of lives given gladly for love of country.

Warfare as blood sacrifice: it's what the leaders and soldiers said. It's what actually happened.

"I don't believe it."

The desire not to know is a fundamental human desire.