Final answer:
The correct answer is option 4. The United States was called the "Arsenal of Democracy" because it provided a significant amount of the weaponry that the Allied forces used to defeat the Axis powers during World War II.
Step-by-step explanation:
Why was the United States called the "Arsenal of Democracy"?
In 1940, the term "Arsenal of Democracy" was used to describe the United States' role as a primary supplier of military equipment to the Allied forces during World War II. This terminology reflected both the idealistic role the nation saw itself playing in the promotion of democracy and its economic power. President Franklin D. Roosevelt mobilized the country to support the war effort, converting peacetime industries into wartime munitions factories. American industrial output became crucial in the fight against the Axis powers, exemplified by feats like the Ford Motor Company producing a B-25 bomber every hour.
By the end of the war, the United States was responsible for 50% of the world's manufactured goods, even though it only comprised 5% of the global population. The production capacity and support for democratic nations during the war thus justified the label "Arsenal of Democracy."
The correct answer to the provided question, out of the given options, is option 4) The United States provided much of the weaponry needed to fight the Axis powers.