In my experience, people- well, men, because it's pretty clear that this discussion has not at any point been about the other 51% of the species- spend a lot of time exaggerating their preparedness for violence. Men convince themselves that they are one bad day away from becoming John McClane. That's why John McClane exists, because the idea that within every regular shlub beats the heart of a vengeful killing machine is an appealing fantasy. Very few are prepared to admit, to themselves or others, that their "flight" response dwarfs their "fight" response in the great majority of situations. There's a reason that these soldiers, normal men, are subjected to rigorous training to convince them not to flee or hide as soon as they are fired upon, like any normal person would do.
If you want to appeal to our misty and bestial past, then consider that we are descended from the cavemen who managed not to die, not from the cavemen who went down in a frenzy of Spartan bloodshed. The evolutionary impetus to avoid violent confrontation is far stronger than the impetus to engage in it. There's a reason why most dueling animals spent more time posturing than fighting, and most of the fight sparring rather than actually trying to gore each other. And it's why these primitive humans, killing their prey with their bare hands, were mostly strangling exhausted gazelles rather than battling lions.
Humans are naturally conflict-averse. It's one of our great virtues, as a species. The reason you get creatures like Kavanaugh is not because we are naturally prone to be destructive towards people, but because hierarchical societies allow them to regard other people as something less than people. Kavanaughs and his ilk behave as they do because for them, violence isn't really conflict, because there is no risk of anybody matching that violence. It is merely the exertion of will. If the powerful suddenly discover the human-shaped objects surrounding them are allowed to hit them back, that their attempts to exert their will has consequences which they cannot control, we'll quickly found that most of them are profound cowards. Ask the good citizens of Paris or Petograd, they'll tell you a thing or two about it.
"there you go, bringing class into it again." "but that's what it's all about!"