LitCharts assigns a color and icon to each theme in The 5th Wave, which you can use to track the themes throughout the work.
Trust and Belief
Survival and Perseverance
Warfare and Dehumanization
Family
Summary
Analysis
Cassie went back and secretly saw Vosch and the two soldiers loading a Humvee with a round object that looks kind of like one of the drones. They had their masks off and look like humans. The soldiers left and the object starts to pulse with light, and it looked like an eye—Cassie realized it might be the Eye the soldiers were talking about earlier. Suddenly, Cassie realized she was in danger and ran away. She made it into a ravine just as the object exploded, her eardrums popping.
While other parts of the novel suggest how surveillance can be dangerous, this passage makes that connection literal, as Cassie barely manages to escape an exploding eye-shaped bomb. The fact that the soldiers look like humans—and might even be human—shows how Cassie can’t even trust her own eyes to let her know what’s safe and what’s dangerous in this post-apocalyptic world.