Kien turns his rage on Phuong in this moment, and though it’s possible that this is just an instance of misplaced anger, the fact that he calls her a “whore” possibly suggests that he holds her own rape against her, as if it’s
her fault that a group of men violently took advantage of her (which, needless to say, it’s not). Given this tense interaction, it’s unsurprising that they later find it difficult to move on from the horrors of war. On another note, it’s significant that the first person Kien truly injures (and possibly kills) in the war is a fellow Northerner—a good indication that war isn’t as straightforward and clear-cut as he has been trained to think.