Private John Bartle, most often known by the nickname "Bart," is the novel's first-person narrator and protagonist. Bart narrates the novel from a retrospective remove, looking back on the events described with the benefit of hindsight. As such, many of the novel's passages take on the introspective, lyrical quality of reverie. Bart, as the primary lens through which we experience the novel, reveals himself to be a thoughtful, honest, and insightful character, as well as a flawed one. When reflecting on his time in the army, Bart says, "It had been good to me, more or less, a place to disappear. I kept my head down and did as I was told. Nobody expected much of me, and I hadn't asked for much in return" (34). This idea of disappearing will return later in the novel, after Bart first returns home to Virginia, but here we see Bart as an average joe, nobody special, and someone most readers can relate to. A few pages later, after Bart meets Murph, we see something of their shared background, each "from a place where a few facts are enough to define you" (37). 

Bart, who is 21 when he goes to war, is a few years Murph's senior; Murph is just 18.Whether Bart wants to or not, he functions in a sort of mentor role for Murph, and most of the time this responsibility seems to chafe at him: "I didn't want to be responsible for him," Bart says after the battle in the orchard (120). Much of the novel revolves around Bart and Murph's relationship, which is a conflicted one for Bart. Near the end of Murph's life, in Chapter 8, Bart worries, "I don't even know if we were actually close" (166). And yet, as readers, we can pick up on things that perhaps, even several years removed from the actions he is narrating, Bart cannot see for himself. For instance, in the opening chapter, Bart says, "Murph's breath was a steady comfort to my right. I had grown accustomed to it" (6). Later, in the same chapter, Bart offers, "Murph and I leaned against each other until the weight of our bodies found their balance" (16). These gestures mean a lot and establish for the reader the emotional closeness of the two, as seen through these instances of physical closeness.

As a narrator, Bart is reflective and unflinchingly honest, and often self-critical. In Chapter 7, while dealing with intense bouts of PTSD, Bart has an extended, stream-of-consciousness passage in which he berates himself for being a coward, saying, "cowardice got you into this because you wanted to be a man and people made fun of you" (145). Later, when the captain from C.I.D. comes to arrest him, he says, "That's what my cowardice was: I accepted the fact that a debt would come due, but not now, please not now, anything for a little more time" (180). These aspects of his character, especially when combined with the insightful/lyrical/philosophical passages throughout the novel, have the effect of endearing Bart to the reader. Rather than passing judgment on him, the reader is invited to understand, because Bart is already passing judgment on himself. The entire novel, told in Bart's voice, boils down to his own attempt to understand himself and what happened, and how he can move on after having experienced the things he has.

Private Daniel Murphy, or Murph, is one of the novel's key figures and serves almost as its raison d'être, since it is his death that hovers at the center of the novel and that haunts Bart so thoroughly, providing Bart with the motivation to reflect so deeply on his experiences. We are introduced to Murph briefly in Chapter 1, before moving back in time in Chapter 2, to see how they first met. Bart gives his first impression of Murph: "In truth, he didn't seem special then" (32). However, even in this phrasing, we can intuit from the "then" that this perception changes at some point, and Bart does find Murph to be special. In these early chapters, Murph comes across mainly as naive and vulnerable, someone to be protected and looked after, especially when compared to Sterling. As Bart narrates, "some people are extraordinary and some are not" (35). 

It is in this ordinariness, though, that we see Murph's humanity come through the most. In one of the novel's more touching scenes, when the platoon is between battles and receives mail, Murph gets a breakup letter from his girlfriend back home. Bart describes Murph’s face as "full of naivete and boyishness, but we were boys then. It makes me love him a little, even now, to remember him [...] sad that his girl had left him, but without anger or resentment, despite being only a few hours removed from all the killing of the night before" (80). There is a sweetness in Murph that is endearing, even if it means he is essentially unfit for war. We also see some of the insight Murph possesses midway through the novel, when Bart is trying to describe what battle feels like, and says Murph had described it best, comparing it to a car accident (93). 

As the novel progresses, and the amount of death and trauma the two experience mounts, Murph becomes increasingly aloof, and Sterling claims that he is "a dead man" (155) because he's already back home in his head. Although Bart laughs this off, he also says, "In a way, I knew it to be true" (156). Finally, Bart catches up with Murph and finds he has been at the medics' unit, loitering to watch a female medic as she would pass in and out of the unit. Bart says, "I thought it was this and not her beauty that brought Murph there over those long indistinguishable days [...] it might have been the last habitat for gentleness and kindness that we'd ever know" (164-65). Finally, after the same medic is killed by mortar fire, Murph loses it. This seems to be the final straw before he wanders off base, naked and alone, drifting in a sort of fugue state. After Murph's death, and after Bart's tour is over, Bart compares Murph to a martyred saint in a church in Germany, and looking over to the images he had admired earlier, such as "beautiful Sebastian, the arrows dangling from his chest" (56). The last image of the novel is Bart imagining Murph's body travelling down the river and out to sea.

Along with Bart and Murph, Sergeant Sterling forms the third leg of the trio of main characters. He is one of the novel's most complex and well-developed characters outside of Bart himself. When we first encounter him, in the opening chapter, Sterling seems like a motivating force in the platoon, the person who gets things done and whom almost wields the real power behind the lieutenant: "Sterling seemed to know exactly how hard to push the LT so that discipline remained. He didn't care if we hated him. He knew what was necessary" (17). The first chapter ends with a firefight, during which Bart remains frozen until Sterling goads him into action, with Bart remembering, "I hated him. I hated the way he excelled in death and brutality and domination. But more than that, I hated the way he was necessary [...] I hated the way I loved him when I inched up out of the terror and returned fire" (19-20). This mixture of love and hatred define Bart's feelings toward Sterling throughout the novel. In many ways, Sterling functions as a father figure for Bart (and, to a lesser degree, Murph), reflecting the complex and often-contradictory feelings fathers and sons can have for one another. 

In Chapter 2, when the narrative retreats in time to when Bart meets Murph in training, we find that it is Sterling who first foists responsibility onto Bart for Murph's well-being, telling Murph, "I want you to get in Bartle's back pocket and I want you to stay there" (33). Bart's initial reaction to Sterling is that "He was hard, but fair, and there was a kind of evolutionary beauty in his competence" (33). Later, Bart says Sterling is "extraordinary [...] though I could see at times that he bristled at the consequences of this condition" (35), revealing the respect Bart has for him, and the empathy he has for the difficulty of Sterling's position. One of Sterling's defining characteristics is "a kind of elemental self-sacrifice, free of ideology, free of logic" (43), as Bart sees it. Sterling has essentially already sacrificed himself to Mother Army, defining himself solely through his role within the military, which in part is defined by brutality.

There are a number of instances where Sterling’s brutality rise to the surface. When they are in Germany, he roughs up a female bartender in a brothel (66); when he learns that Murph's girlfriend broke up with Murph in a letter, he says, "I'd kill a bitch" (81). Murph, looking through his scope catches Sterling doing something ambiguously disturbing with a body (95), and after getting the Iraqi cartwright to help them dispose of Murph's body in the river, Sterling (with Bart's complicity) shoots the cartwright in the face (211). It is this brutality, and Bart’s memories of it, that make Bart physically nauseous,and yet, after the brothel scene, when Sterling abuses the woman and threatens Bart, Bart still covers for Sterling the next morning and offers Sterling a thank you.

By the end of the novel, Bart comes to better understand and sympathize with Sterling, after Sterling has killed himself. Bart realizes Sterling "was not a sociopath," but rather so caught up in his role in the military that Bart is "not even sure if he would have realized he was permitted to have his own desires and preferences" (187). In the end, Bart "still believe[s] in Sterling now because [Bart’s] heart still beats" (187). No matter what else he did, Sterling helped Bart survive. Also, for a man so caught up in following orders and self-sacrifice, Bart almost seems to admire the way Sterling ended his life, saying, "He'd been able to do only one thing for himself, truly for himself, and it had been the last act of his short, disordered life" (188).

Murph's mother, LaDonna, is one of the most important minor characters that appears in the novel. Chapter 2 begins with her: "Mrs. LaDonna Murphy, rural mail carrier, would have only needed to read the first word of [Bart’s] letter to know that it had not been written by her son" (29). The formality of including her full name gives her a stately and formal position in Bart's memory and therefore also in the novel itself. By the end of Chapter 2, we see her asking the impossible of Bart: to "promise [her] that [he'll] take care of [Murph]" (47). This promise that she manages to secure from Bart haunts him throughout their tour, both when Murph is still alive, and also after Murph is killed. The forged letter mentioned at the beginning of the chapter and the misinformation surrounding her son's death prompt Mrs. Murphy to push the military for explanations and for accountability, actions that propel the novel to its inevitable conclusion, seen most strikingly in Chapters 9 and 11, when the captain from C.I.D. shows up on Bart's door with the letter in his hand and arrests Bart. When Mrs. Murphy comes to visit Bart in prison, it proves to have a palliative impact of him, helping heal some of his psychic wounds through her honesty and lack of pity: "She hadn't offered forgiveness and I hadn't asked for it. But after she left, I felt like my resignation was now justified, perhaps hers too, which is a big step nowadays, when even an apt resignation is readily dismissed as sentimental" (223).