I’m retired military, but was never in combat. However, the training you receive kicks in pretty quick when someone is shooting at you. My son’s career military and has been shot at, fired back and killed.
He remembers his unit’s first engagement in Afghanistan. They were ambushed. He said there is a moment of hesitation when you’re thinking this can’t be happening to us. Then the training kicks in and you fight back. Second engagement there is no hesitation and everyone starts shooting. In this engagement you’re a lot more focused and are actually thinking and maneuvering. In the first and second engagements you’re too busy trying to stay alive to give much thought to the people you’re killing. Third engagement you’re on autopilot doing your job. But you’re thinking if they would just leave us alone we’d go home because there would be no one to fight. By the fourth engagement you’re angry. This anger manifests itself in aggressiveness and frankly not caring about the people you’re killing. You’re job is to ultimately go home to your family
As for me, I think I would react similarly if anyone were to attack me. People have three choices when confronted—flight, fight or surrender. It is not my nature to flee or surrender. Conceding that I have not been tested, I don’t think killing someone trying to do me harm would bother me all that much.
For the average person today, most likely having no military training, the big moment is making the decision to defend yourself—with your hands/feet or a gun. That is the moment one chooses not be a victim. I think it natural to be a little remorseful that the perp forced you to kill him/her. But being elated at just having survived the encounter will pretty much negate any feelings of guilt over the longer term. I think normal people, in thinking about their experience from time to time, would wish they were never forced to kill anyone. But I doubt they would dwell on it much.
Life moves on.
Again, admitting I’ve not having been tested, I believe it would be as easy for me to kill a feral human being attacking me as it would a feral animal attacking me.
Never had to use Army combat training but you’re very right. Even in training, confusion rules. Shooting and defensive skills require training to develop automatic responses. Priop planning & preparation prevents piss poor performance. Go to the range, practice quick fire.