Inferred Holocaust: In the wake of the pandemic, most of the babies and small children across the world would have died from starvation due to no adults around being able to feed them. In addition, many more children would die in the battles over dwindling food and water supplies. It is likely that at the time of the story, there are only one billion humans left on Earth.
Moral Event Horizon: Crossed by Barry when he murders Jennie because she is pregnant. Crossed twice more when he murders Dylan, and tries to murder the Indian chief Running Bull.