What is the point of the persistent repetition of the words "the things they carried"?
The phrase "the things they carried," which is also the title of the first short story in the book and the collection as a whole, is a way for Tim O'Brien to emphasize that the American soldiers he depicts in the Vietnam War and after carry substantial burdens in numerous ways.
"The things they carry" literally refers to physical objects carried by the soldiers. These items are most obviously the equipment they need for war, like weapons and ammunition, as well as other necessities, like food and water. Material items also hold metaphorical or abstract meanings to the men. For example, some soldiers superstitiously carry items to help keep them safe, like a rabbit's foot or a Bible, which provide comfort and distraction. They carry items from home to remind themselves of their families and to keep them feeling human in an inhumane set of circumstances. Lt. Jimmy Cross, for example, carries letters from Martha, a woman he loves at home. They did not have much of a relationship before the war, but he holds on to her letters to keep the hope alive that he may return to a normal life when he goes home. Unfortunately, he also blames these letters and his obsession with Martha for the death of one of his men, Ted Lavender, because Jimmy feels he has been distracted from his duties to his men. So he burns the letters and rededicates himself to his unit, but the story leaves us wondering whether that sacrifice comes at the expense of Cross's humanity.
The men also "carry" emotions, like fear, that are natural for any soldier during war. However, extra stress is added by the men's perceived need to hide their "weaknesses," like their anxiety about dying in battle or their concern that they will appear to lack courage or bravery in the company of their fellow soldiers. They carry a desperate desire to go home unharmed and alive—to return to a life that is not marred by constant danger. They carry the atrocities they have witnessed and committed as part of the war effort. These psychological burdens seem to weigh more heavily on the men than the physical weight of the items they carry to fight and survive in war. Thus, O'Brien is able to comment on the psychological toll war takes on those who experience it first hand.
O'Brien uses repetition of the words "the things they carried" in part to visit and revisit episodes such as Ted Lavender's death. Rather than present Lavender's death in a straightforward, chronological narrative, O'Brien scatters details about his death throughout the story "The Things They Carried."
For example, the first time Lavender is mentioned, O'Brien writes about him: "Ted Lavender, who was scared, carried tranquilizers until he was shot in the head outside the village of Than Khe in mid-April." O'Brien later writes that Lavender carried dope, 20 pounds of ammunition, and a poncho that is used to wrap him up and carry him after he is shot. He is then carried aboard a chopper. Even after this point in the story, O'Brien continues to add details about what Lavender carried, such as a starlight scope. The other soldiers continue to talk about what Lavender carried, including his supply of tranquilizers, even after Lavender's death. The repetition of what Lavender carried, sprinkled throughout the narrative, means that the story of his death is told in a fragmented way. This is the way that the other men in Vietnam might have experienced his death. It was so sudden and so jolting that it can only be recalled in short bursts of memory. By using repetition and the scattering of short details, O'Brien tells of Lavender's death the way the other soldiers might have experienced it.
O'Brien uses the repetition of these words to create an unmistakable realization that the men are always carrying “things,” whether it is a physical weight or an emotional weight. The repetitiveness of the words lets the reader, in a sense, feel how the soldiers feel. The soldiers are unable to forget the weight of the “things they carry,” and by repeating the words, the reader is not able to forget the weight either. The sense of annoyance that the reader may feel by the constant repeating of the words is a technique used by O’Brien to connect the reader to the characters. The soldiers may also feel frustrated that they do not get a reprieve from the constant burden of their weights.