Even in the border states during CW1, it was rare for the women and children left behind to be murdered.
It was SOP in Bosnia, 100% SOP. An American CW2 would be Bosnia X 100.
Read “Seasons In Hell” about Bosnia. It’s in your library.
If say, Texas seceded from the Union now, do you really think there would be Bosnia II inside of Texas? It would be a new country under the same management, the Gov becomes Pres, No blood shed internally, maybe from the outside, that's different.
Your whole premise that we would behave like Bosnians is really insulting in some ways.....
The states are designed to operate as independent countries. Your premise that if the fedgov disappeared chaos reigns plays right into the statist's playbook.