I couldn't
My military training was limited to ROTC and reserve officer status. I was never exposed to that kind of training and frankly, discipline has never been my long suit. Even after training I am not sure anyone can know what they would do in a real situation.
Oddly, I have no doubt that I could push a button that would launch a nuclear retaliation but I could never squeeze one off at a child.
I was no stranger to violence in my youth and I have known and associated with many violent and ruthless people in my life, (a friend to some but never a friend of theirs), but there was always a code that excluded women and children.
No judgment intended, with the right indoctrination I might be different.