Imagine a class full of history students who are sick and tired about learning history. To them, it's a tired list of war after war, and the nations are changing and evolving, but to them, it is just more facts to memorize for tests. Someone might here about the Vikings invading Paris hundreds and hundreds of years ago, but to them, it sounds like just another conflict. Dak, Sera, and Riq have a different point of view in this novel.
To Dak, Sera, and Riq, suddenly, history has come alive. They realize that the facts they had memorized in history class are actually records of real lived time, experiences that human beings really had. That makes them unable to pick sides, and it restores the gravity of warfare back. Whereas before, war was just another kind of fact, suddenly it occurs to them that they want to survive. Beyond the justice of who "should" win, they are forced to admit that secretly, they just want to see the least amount of bloodshed possible.
In a way, the novel therefore teaches empathy, but not the lateral empathy of empathizing with those who are different than you (that one typically learns from literature and art), but a new kind of empathy. They feel empathy for the humans who lived and died in ages past, understanding the value of their human life. Also, they realize that modern eyes don't work for judging the behaviors and decisions of those in the past, because the very assumptions that govern the kids' modern sensibilities are in the process of developing, so there is no analog for judgment.
