The Ukraine-Russia war is teaching all sorts of lessons, but to date no one in Washington or in the U.S. military has learned a single one of them. From The Zman at the zman.com:
Most likely, the first war in human history was one group of guys rushing at another group of guys, swinging fists and anything they could use as a club. It did not take long before a man decided that it was a good idea to use his hunting weapons to ward off these attacks or compliment these attacks. After all, if a gang of men with spears could take down a large animal, the same tactics would work on humans. From there the arms race was on among the human species.
The club was probably the first weapon of war. The spear would be the first tool converted for use in war. The shield was the first tool of war created specifically for use in combat against other men. Unlike the club, the shield was not just lying around waiting for a man to use it in a fight. Unlike the spear, the shield was not something used for hunting. The shield was a practical response to men using their spears to poke at you in a fight. It was the dawn of the arms industry.
We have no way of knowing if any of that is true. The first men were not big on writing stuff down so we are left to speculate. Maybe the crazies are right and people are naturally peaceful until a weapon is introduced. Some guy brought his spear to the clan meeting and this caused the clans to break out into warfare. Perhaps humans were vegetarians, eating what they could find until one guy picked up a stick and then immediately decided to start beating people with it.