Two World Wars that happened in XX century sometimes in most unexpected ways had been a catalyst to growth in numerous industries besides making humanity to suffer losses. War of attrition made to think about food security of all parties to world conflicts. Even national programs that fundamentally changed diet of hundreds of millions people were developed. These events echoing in menus around the world to this day – people started eating more vegetables and fish precisely then.
Military propaganda did not avert from this by spawning plenty of posters that look pretty amusing from modern point of view.