It's exaggerated instincts from all of the man made stimulant drugs we consume.
For millions of years we were like the bears and the wolves and deer and the rabbits and the beaver and all living things.
We fought for our positions and feeding territory and females and just because we liked to fight and see who is toughest or make sure it was known that we claim and hold our territory from anybody who doesn't belong there.
Over time we would get old and the younger males would take over.
Seldom if ever would anybody get killed.
Occasionally as grouping animals other groups would infringe on our territories or females and sometimes natures events would push us within each others territories and group fighting would ensue.
We sometimes hunted in groups too.
Mass killing and mass murder never happened and seldom was anybody killed in the fighting and we never killed women and children.
Stimulated insanity from all of the stimulant drugs we began to consume changed all that and turned us into Kingdoms and Empires with armies of murdering monsters.
Killing and taking all and always wanting more.
Murdering and killing hundreds of millions of women and children and babies.
Lack of empathy and superiority from all of the adrenaline and never once knowing.
Blasphemous any who oppose.