though theprotagonist, who narrates the story, is named O’Brien. This is one of the techniques the author uses to make his fiction more representative of reality. Beyond merely relying on imagery and dialogue to make his stories more realistic, O’Brien’s use of his own name for a character makes the reader question whether the book is based in fact. The verisimilitude woven throughout the book makes it difficult to distinguish between fiction and nonfiction.

O’Brien (as the author, not the character) developed his purpose for writing The Things They Carried after returning from the Vietnam War and learning that most Americans were very ignorant about the dynamics and the actual experience of the war. This was frustrating for O’Brien, who had just lived through it. In response, O’Brien wanted to write a book that would vividly portray the challenges and horrors of being a soldier in the Vietnam War. He succeeded in achieving this purpose with The Things They Carried.

Tim O’Brien’s purpose in writing The Things They Carried is to explore truth through imagination and fiction. O’Brien explains this in the novel when he says,

The thing about a story is that you dream it as you tell it, hoping that others might then dream along with you, and in this way memory and imagination and language combine to make spirits in the head. There is the illusion of aliveness.

With this statement, O’Brien expresses that with some stories, truth can be hard to discern. As a result, memory and imagination might help create a story. In addition, he also suggests that truth is not necessary. He tells the reader, “It’s safe to say that in a true war story nothing is ever absolutely true.” O’Brien is pointing out that absolute truth isn’t always the point of writing the novel. In his case, the stories help the reader understand what war did to people. Readers can empathize with Norman’s displacement, Kiowa’s death, or Mary Anne’s transformation whether the characters were real or imagined. These stories would be no less powerful if they were pure fiction. O’Brien’s purpose is to imaginatively express a certain truth about war—even if that truth is not "absolute." O’Brien is more concerned with writing a story that affects the reader than he is with presenting outright facts.

O'Brien's purpose in writing The Things They Carried is in part to merge fact and fiction. He writes about a character named Tim O'Brien who very much resembles himself, but this character is fictional. Although the author Tim O'Brien  actually fought in Vietnam, the Tim O'Brien character is a work of fiction. 

Creating this fuzzy distinction between fact and fiction is one of O'Brien's purposes, as he wants to tell the story of his war experiences without being chained to pure fact. By writing a work of fiction, he believes that he is creating an even truer story about what Vietnam meant to the people who fought in it. The important element of his book is the emotions that attend the characters in the war, not the factual details of their lives. Additionally, telling these emotional stories is another of O'Brien's purposes in writing the book. 

O'Brien's purpose in telling The Things They Carried is twofold; to tell a war story, and to explore the purpose of storytelling itself.

Beginning with "How to Tell a True War Story," O'Brien begins examining misconceptions and truths surrounding the experience of war and the telling of stories about it. Partway through the chapter he begins delivering strings of statements, which often seem contradictory, concerning the telling of these stories:

A true war story is never moral. It does not instruct nor encourage virtue, nor suggest models of proper human behavior, nor restrain men from doing the things men have always done. If a story seems moral, do not believe it.

It's important, when reading this section, to keep in mind how prominently placed "a work of fiction" is on the title page of this book. O'Brien is not setting out to tell a true story himself; and being only partway through the novel, the reader is left to wonder whether any moral lesson or instruction is forthcoming.

Similarly, in "The Lives of the Dead," O'Brien speaks more broadly about the purpose and construction of stories in general. He describes stories as a kind of wish-fulfillment with lines like:

But in a story, which is a kind of dreaming, the dead sometimes smile and sit up and return to the world.

and

The thing about a story is that you dream it as you tell it, hoping that others might then dream along with you...

At the end of the book, the author discusses why he tells stories - to keep others alive and to deal with the pain of his own losses.