Question

what economic impact did the first world war have

Answer 1

From 1915 the US made tons of loans to the UK to help them in their war effort. It is not a stretch to say that WWI was the major factor in contributing to the "Roaring 20s" when the US economy boomed. ... The long term effect was that US involvement in the war lead directly to the Great Depression and WWII

Answer 2

The economic history of World War I covers the methods used by the First World War (1914–1918), as well as related postwar issues such as war debts and reparations. It also covers the economic mobilization of labor, industry and agriculture. It deals with economic warfare such as the blockade of Germany, and with some issues closely related to the economy, such as military issues of transportation. For a broader perspective see Home front during World War I.