Three policies that sustain economic prosperity in the u. s. after wwi?

Three policies that helped sustain economic prosperity in the U.S. after WWI:

Three policies were;

The world war 1 which started in 1914 and ended in 1919 also had the United States involved in the war. Even though it had drastic impact on the economies of the European countries, it did not have much effect on the economy of the United States because of some of it's major policies where the most important policy was that of isolationism where the United States did not enter in trade with any of the outside countries. The loans it had given to the Great Britain also helped it to get interest and money.