How does Henry's personality contribute to the plot?

He joined the army with preconceived notions of the inherent glory of war. But the reality of the battles leaves him desperately afraid. In his first battle with the 304th regiment, he flees. His shame prompts him to return and he eventually fights courageously in his second battle. His musings, thoughts, and responses to war are the focus of the book; because of his changing minds and deeds, he matures as the book progresses. He is, at times, arrogant, prideful, cowardly, courageous, and obsessive. Henry maturation enables him to help other scared soldiers. He sees boys who, once like him, are trembling with fear. Henry is able to offer perspective as well as a role model of how humanity in the chaos of war.