Answer:
The United States benefited most from the industry during World War I. Initially, President Woodrow Wilson embraced a neutralist policy during the war, which over time was mutated into a non-military collaboration with the allies, first, and a total entrance to the war, later.
The truth is that the United States maintained its neutrality until April 2, 1917, that is, for almost 3 years the country was dedicated to enlarge its armed forces and raise its industrial production to supply armaments and supplies to the combatant countries, while they could not do them because they were in a critical combat situation. In addition, once the American participation in battle began, it took place in European territory, away from the factories of the Midwest, which could continue to produce.
This situation implied that from the 1920s, the United States became the main industrial power in the world, since it had 3 years of sustained industrial growth, while the rest of the powers had 4 years of stagnation.
