“The bombs were meant to kill people, but they also killed the Earth. Megaton after megaton charred the crust of the planet, not only destroying crucial vegetation but releasing subterranean chambers of poisonous gases. These heavy, dense vapors escaped and lingered near the ground, choking the life from anyone caught in their fog.
Only the tallest of humans could breathe over the clouds of death, and the interbreeding of survivors exaggerated their height even further. The post-apocalyptic world was soon inhabited solely by emaciated giants, disproportionately taller than the disheveled skeletons of buildings the war left intact.
In this new world where survival was paramount, gas masks were the most prized and valuable possessions. If a family did come into ownership of one, it was always worn by the shortest person. This was especially true in the rare occasion of a baby successfully being brought into this cursed domain. The child would breathe exclusively through the gas mask for at least the first decade of its life, if not the first 20 years.” -M.D. Walter