Grenade

Soldiers on both sides are human beings, with families, sweethearts, normal lives back home. They're capable of empathy and kindness but become monsters when they feel threatened and afraid. People can try to hold onto their humanity even in dire circumstances. Bravery doesn't mean not being scared; it means overcoming your fear to do what you need to.

Lots of casualties, some shockingly unexpected. Both protagonists kill. Characters get killed by sniper fire, grenades, flamethrowers, shot at point-blank range. Some who die are civilians, some children, some soldiers in their teens. Group of civilians commit suicide by jumping off cliff when trying to escape soldiers. Soldiers commit suicide to avoid capture or gunfire. One character's hit by bullets, "his body dancing like a broken puppet." Flashback to American soldier's father attacking him with knife because he has PTSD from WWI.

The American soldiers call Japanese people "Japs." Book gives a heads-up that it "contains terminology that was used in World War II," and in an afterword, Gratz says, "calling someone a 'Jap' is offensive and disrespectful. I used this word in my book for historical accuracy, but it's a word you should never use."