(Some spoilers for Hater)
I realized about halfway through that I was forcing myself to get through the book. Never a good sign.
Part of what made Hater so good was how chilling Danny's behavior was after his change. He was 100% certain that he had to kill the Unchanged or they would kill him and during the kills he experience euphoria.
In this book there was a bit of the euphoria but I never found his behavior chilling. While in Hater he acted on instinct in this book Danny spends lots of time whining about maybe not being "good enough" for the rest of the Haters. He feels like he should kill people but in a pretty half-hearted way unless there's actually an Unchanged person near him. It actually feels very like the daily grind of going to his old job except, you know, it's killing people so you can't really identify with him.
It's hard to identify with anyone in this book (besides, maybe, his cousin who we only see for a short time. Maybe we're supposed to identify with Danny's drive to find his daughter, Ellis, except the reason he wants to find her is to care for her and so they can kill people together. So I wasn't rooting for that reunion.
I'm not sure if this is supposed to be a commentary on terrorists or unending war. There are some explicit references to terrorism so it might be that. Whatever the intention was, what's missing is passion. People may continue to fight a war long past the point where the original insult is forgotten. But they do it so that one day the war will be over and future generations can have a better life. People become terrorists because they believe in an ideology, because they think someone is occupying their land, because they think someone is keeping them from living their lives the way they want to, or teaching their kids the way they want to, or even because they don't believe in ideology but know if they become a terrorist, their family will be looked after financially.
The Haters don't fight for anything. There's a line or two about after the Unchanged are dead but there's no passion for it. They fight against the Unchanged because they believe the Unchanged will kill them as soon as they realize what they are (of course, they wouldn't kill the Haters if the Haters weren't killing them). The problem is there's the occasional moment of fear but mostly the Haters are portrayed as feeling vastly superior (physically) to the Unchanged. So instead of a threat the Unchanged feel more like an annoyance.
The Haters don't care about the future, or individuals. They only care about the fight. They only care about children insofar as Hater children make excellent fighters. I had the distinct impression that if the Haters managed to eradicate all of the Unchanged they wouldn't know what to do with themselves. Maybe sit around all day and talk about how great it was when there were Unchanged to kill.
I realized by the end of the book that I couldn't imagine an ending to this trilogy that would leave me feeling satisfied. The Haters win and then sit around or they get wiped out and the Unchanged try to rebuild. Maybe there's a cure and I guess the Unchanged feel horror at what they've done. But none of that would satisfy me which is why I'm not going to bother with the third book.
The real shame is that I think there was a genuinely moving and meaningful story to tell here. One of the characters says that the Unchanged are the true Haters because they promised "never again" after World War II but the moment they felt threatened they built slaughterhouses to kill the Haters in gas chambers. The problem is, you can't tell that story from the point of view of the Haters because they lack the emotional capacity for it.