OpenStax
Open Stax: Americans and Great War 1914 1919: The United States Prepares for War
Details what America did to prepare and execute its entry into World War I, and how the government used propaganda to win public support for the war effort.
Smithsonian Institution
National Postal Museum: Victory Mail
Learn all about "victory mail," the expedited wartime posting of letters written to and from soldiers serving in World War Two.