1938 Horrors Of War #155, Cantonese Parade Through Coffin-Lined Streets 💥
The 1938 bubble gum card set, produced by Gum, Inc., was designed to "teach peace by exposing the horrors of war" and featured the tagline: "To know the HORRORS OF WAR is to want PEACE". 
President Roosevelt found the initial 240-card series helpful in illustrating the atrocities occurring in the Spanish Civil War, the Ethiopian War, and the Chinese-Japanese War to the American public.
FDR didn't officially endorse the cards, but used of them to promote U.S. public awareness of international dangers. This prompted some U.S. senators to criticize him for engaging in "bubble gum diplomacy".