The themes in Tim O'Brien's "The Things They Carried" are the physical and emotional burdens carried by soldiers, the subjective nature of truth in storytelling and fear and shame as a motivation in war. Tim O'Brien uses his own experiences to develop the themes in his story that follows a platoon of infantrymen in the Vietnam War.
The title "The Things They Carried" emphasizes the first theme. The soldiers carry around the burden of their large packs, but they also carry the burdens of fear, guilt, grief, a need for love and comfort. The physical items the characters carry help to illuminate the emotional burden they shoulder. According to SparkNotes, Henry Dobbins carries around his girlfriend's pantyhose, which reflects his emotional burden of a need for love and comfort.
O'Brien also highlights how subjective truth is in war stories where there has been terror and trauma. At times it is difficult for soldiers to separate their nightmares and fears from reality. O'Brien clarifies through this theme that it is not so much the facts that make up a story or experience, rather the way the experience is internalized by the soldier.
The third theme communicates the difference between going to war out of patriotism and going to war out of fear of being called a coward. Once the soldiers are in Vietnam, their actions are dictated by a desire for social acceptance among their peers (platoon) that leads them into many dangerous situations.