The second factor that enables killing from behind is a process in which close proximity on the physical distance spectrum can be negated when the face cannot be seen. The essence of the whole physical distance spectrum may simply revolve around the degree to which the killer can see the face of the victim. There appears to be a kind of intuitive understanding of this process in our cultural image of back shooting and back stabbing as cowardly acts, and it seems that soldiers intuitively understand that when they turn their backs, they are more apt to be killed by the enemy.
