The use of propaganda was very successful in both World War I and World War II. We needed to convince our people that both of these wars were right for the United States and to get Americans to be supportive of our war effort.
In both world wars, the government launched a big propaganda campaign to sway Americans. The government needed to get people to grow their own crops with victory gardens, reduce the consumption of other food items, join the military, buy war bonds to help finance the war, and encourage people to work in the factories that produced essential war materials. There were pamphlets and posters produced to constantly convey these messages. Speeches were also given. People were also reminded to be careful about what they said in public about the war effort and war activities.
The British and Germans also had a propaganda campaign, especially during World War I when we were neutral for over two years. Each side tried to get into the minds of Americans with their propaganda methods. Each side wanted American help and support in World War I. The British were more successful than the Germans in doing this. Propaganda was very important in both world wars.