Ishmael is kind of an odd duck protagonist, since he's not terribly central to a lot of what happens. The story is largely focused on the murder trial and all the historical events and prejudices that have shaped its progress, so what is this lovesick reporter-newspaper runner doing at the heart of it?
Okay, well, despite the fact that he remains largely on the outside of the novel's central action, it's his inner life that we as readers follow most consistently throughout the course of the book and are asked to invest in. Of all the characters, he gets the richest backstory and history and the most in-depth psychological probing. So, let's dig in, figure out what this dude is all about, and explore why he's such an interesting choice for a protagonist...
Ishmael served his country during World War II, losing an arm in the process (and enduring all kinds of horrific things, including watching his friends and acquaintances die in battle—lots of them). All that has left Ishmael a little... off—and hey, we can understand why.
However, somewhat surprisingly, Ishmael seems a lot more focused on and traumatized by the fact that he lost his high school girlfriend, Hatsue, than anything else. Things went south for them when she was forced to leave San Piedro for a Japanese internment camp during World War II.
With a growing sense that things wouldn't end well for them if they continued their secret romance, Hatsue rejected Ishmael's combination sexual advances-marriage proposal (seriously, dude?) right before she left. Then, she wrote him a letter from the internment camp saying she did not love him and they could never be together.
Even though one could argue that Hatsue had the fuller plate of no good, very bad things happening at that point (you know, on account being uprooted from her home and imprisoned), Ishmael was pretty single-mindedly focused on his own misery. Then, shortly after Hatsue left, the heartbroken Ishmael ended up going off to fight in the Pacific, where he continued to focus on the fact that Hatsue broke up with him. It seems like his misery was compounded by the horrors of war (rather than vice versa), which seems a bit funky.
Ishmael is frequently compared to his father, Arthur Chambers, who was a highly-respected and beloved newspaperman. Unfortunately, the comparison is often not favorable. Ishmael sets up the contrast himself early on when he remembers how moral and loyal his father was: "He was, his son remembered, morally meticulous, and though Ishmael might strive to emulate this, there was nevertheless this matter of the war—this matter of the arm he'd lost—that made such scrupulosity difficult" (4.19). For sure, as we find later in the novel, Ishmael's moral compass is a bit out of whack.
In Ishmael's view, the war scooted him off the life path that made his father so admired and well-liked. Ishmael is neither of those things, possibly because he finds it hard to take people seriously: "He understood that they were only animated cavities full of jelly and strings and liquids. He knew, for instance, what brains looked like spilling out of somebody's head" (4.19). Yikes. As a result, "He didn't like very many people anymore or very many things, either. He preferred not to be this way, but there it was, he was like that. His cynicism—a veteran's cynicism—was a thing that disturbed him all the time. It seemed to him after the war that the world was thoroughly altered" (4.19). So, yeah, he's not exactly a people person like his dad was; it seems like the war has made it hard for him to find meaning in human interactions.
Ishmael isn't the only one who picks up on his peculiarities and differences from his father. The bailiff for the Miyamoto trial, for example, reflects on Ishmael's, er, uniqueness when he has to usher Ishmael out of the courtroom, where he has been sitting idly and daydreaming: "Ed Soames watched him impatiently. A strange bird, he told himself. 'Bout half the man his father was. Maybe the missing arm had something to do with it. Ed remembered Ishmael's father and shook his head, disconcerted. He and Arthur had been friendly enough, but the boy was not someone you could speak to" (22.17). Want to guess what Ishmael was thinking about? Yup, that's right—Hatsue.
So, yeah, even with the trial and snowstorm going on (and all manner of other unpleasant memories intruding on his thoughts), Ishmael remains pretty obsessed with Hatsue throughout the novel, focused on ways to get her to connect with him.
In fact, he's so consumed with longing for Hatsue that, when he comes across evidence that could exonerate Kabuo, he considers not bringing it forward and just writing an article echoing Hatsue's view that the trial has been biased. His goal in that, ostensibly, would be to look like he did something to help her and her family while actually doing nothing to prevent Kabuo from being executed (which would remove him as an obstacle to Hatsue's heart)—a pretty dirty trick, if you ask us.
However, he comes to his senses when he re-reads (for the second time in the course of the novel) the letter Hatsue wrote him as a teenager to break things off. He realizes that there was once an aspect of himself that Hatsue admired, but this was "a part of himself he'd lost over the years" (31.20). Perhaps in order to make some strides in getting that part of himself back, Ishmael then hauls booty over to the house where Hatsue is staying with her parents and hands over the evidence.
With this gesture, he finally lets Hatsue go. Better late than never, Ishmael.