These once normal men have become brutal killing machines in the time of war. The Lieutenant orders the last of the Chinese soldiers to be killed with a baseball bat. The soldier ordered to perform this carnage obeys without question. The soldier has been emotionally scarred due to the horror of war. He is a changed man.
War is an entity that grinds down minds, bodies, and souls.
In their stories, O'Brien and Murakami thoroughly demonstrate this change of the individual during the time of war. Both authors show how war turns the average person in society into a man struggling with himself emotionally. They show how men are changed forever.