Which war or conflict allowed american farmers to make a great deal of money?

The first World War

Explanation:

Towards the beginning of the 20th century, the United States advanced to other countries in the matter of production, becoming the first industrial power, but this situation changed during the year 1914, in which the First World War began and the US decreased its growth, but This would not last long. Due to the great war effort of the European countries, the USA returned to be the producers of war material and above all they were the first in the volume of food production for the powers at war.

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