An interesting paradox. At 17 I enlisted in the Marine Corps. The reason? There was a war going on and I didn’t want to miss it, seriously. Although I grew up with hunting and fishing I was no killer. The killing people part of going on was abstract. Many young men of my vintage enlisted, accepted being drafted, ran from the draft or avoided it through privilege. I could in no way make a generalized statement about us other than we were largely man children. Under developed pre-frontal cortex's not prone to ask if that’s a good idea.
You are exactly correct about the effort in taking basically good kids and creating a killer. I’ll not describe the process except to say they put some stuff into our heads. Those who got their combat got some more stuff in their heads. But we became a part of a highly cooperative group. A brotherhood stronger than anything we would return to in civilian life.
Here’s the important part. When we came home and returned to civilian life there was no effort to undo the mess that they put into our heads. Not a single lecture or pamphlet, just a DD-214 release from active duty. Bye. It was as if they didn’t understand or didn’t give a damn. PTSD wasn’t a thing back in my day but there was the idea of the deranged ticking time bomb Vietnam veteran in TV shows and movies, and then we were forgotten. Of course there was the warm welcome home we received that was icing on the alienation cake.
This was all to say that they gave us a family that for many was a stronger bond than with their genetic family and had the attributes that you site for the non-violent humanity. But also describes violent gangs.
I don’t know how we escape the situation that now exists. Since there are non-peaceful people who see the peaceful ones as people who will die on their knees instead of on their feet and as easy prey. They are not just a propaganda boogie man. This is no longer the world of the ancients, so are we a different people to our core now?