Answer:
World War I took the United States out of a recession into a 44-month economic boom. 30 Before the war, America had been a debtor nation. After the war, it became a lender, especially to Latin America. U.S. exports to Europe increased as those countries geared up for war.
After the war ended, the global economy began to decline. In the United States, 1918–1919 saw a modest economic retreat, but the second part of 1919 saw a mild recovery. A more severe recession hit the United States in 1920 and 1921, when the global economy fell very sharply.
World War I destroyed the global integration of capital markets. Germans were not even allowed to trade on the London Stock Exchange for years after the war was over. London lost its place as the center of global finance during the war as its role as the center of global finance was passed on to New York.
WWI was a war that affected civilians on an unprecedented scale. Civilians became a military target, with the economic impact of WWI, meaning that there were shortages of all produce, most importantly food supplies. Consequently, rationing of bread, tea, sugar and meat was introduced.
-Astolfo