<P> Although the United States did not have food rationing in World War I, it relied heavily on propaganda campaigns to persuade people to curb their food consumption . </P> <P> Through slogans such as "Food Will Win the War", "Meatless Meals", and "Wheatless Wednesdays", the United States Food Administration under Herbert Hoover reduced national consumption by 15% . </P> <P> In summer 1941 the British appealed to Americans to conserve food to provide more to go to Britons fighting in World War II . The Office of Price Administration warned Americans of potential gasoline, steel, aluminum, and electricity shortages . It believed that with factories converting to military production and consuming many critical supplies, rationing would become necessary if the country entered the war . It established a rationing system after the attack on Pearl Harbor . </P> <P> Tires were the first item to be rationed by the OPA, which ordered the temporary end of sales on 11 December 1941 while it created 7,500 unpaid, volunteer three - person tire ration boards around the country . By 5 January 1942 the boards were ready . Each received a monthly allotment of tires based on the number of local vehicle registrations, and allocated them to applicants based on OPA rules . There was a shortage of rubber for tires since the Japanese quickly conquered the rubber - producing regions of Southeast Asia . Although synthetic rubber had been invented before the war, it had been unable to compete with natural rubber commercially, so the US did not have enough manufacturing capacity at the start of the war to make synthetic rubber . Throughout the war, rationing of gasoline was motivated by a desire to conserve rubber as much as by a desire to conserve gasoline . </P>

Why did the us use rationing during ww2
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