Final answer:
The United States mobilized for WWI through the Selective Service Act, propaganda campaigns, measures like rationing and selling bonds, and mobilizing industry for war production.
Step-by-step explanation:
The United States mobilized to join WWI through various means. One of the key methods was the implementation of the Selective Service Act in 1917, which required all men between the ages of 21 and 30 to register for military service. This act helped to rapidly expand the U.S. Army and provide manpower for the war effort.
The federal government also launched propaganda campaigns to generate support for the war and encourage recruitment. Additionally, the government imposed measures such as rationing, increased taxes, and the sale of war bonds to fund the war.
Furthermore, the United States worked to mobilize industry for war production. The War Industries Board was established to oversee and coordinate the production of military supplies, while the government encouraged and subsidized industries to increase production of weapons, ammunition, and other war materials.
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