During World War I, the military needed enough food to fight, and civilians back home sacrificed so that they had it. But there weren't any treats. In fact, ice cream was considered "not essential," so the sugar that would have gone into its manufacture was diverted elsewhere, despite the pleas of the ice cream industry. That would change drastically over the next two decades, as Americans turned to ice cream during Prohibition as a substitute for alcohol, and then during the Great Depression as a rare affordable treat. Ice cream came to be associated with the American way of life. So when the U.S. joined in World War II, ice cream went with them.
In 1942, as Japanese torpedoes slowly sank the U.S.S. Lexington, then the second-largest aircraft carrier in the Navy’s arsenal, the crew abandoned ship—but not before breaking into the freezer and eating all the ice cream. Survivors describe scooping ice cream into their helmets and licking them clean before lowering themselves into the Pacific. By 1943, American heavy-bomber crews figured out they could make ice cream over enemy territory by strapping buckets of mix to the rear gunner’s compartment before missions. By the time they landed, the custard would have frozen at altitude and been churned smooth by engine vibrations and turbulence—if not machine-gun fire and midair explosions. Soldiers on the ground reported mixing snow and melted chocolate bars in helmets to improvise a chocolate sorbet.
Read more about the American obsession with ice cream, and how the frozen treat went to war, at the Atlantic. -via Metafilter