Answer:
World War I was one of the great watersheds of 20th-century geopolitical history. It led to the fall of four great imperial dynasties (in Germany, Russia, Austria-Hungary, and Turkey), resulted in the Bolshevik Revolution in Russia, and, in its destabilization of European society, laid the groundwork for World War II.
Step-by-step explanation:
America and many other great countries wouldm't have been able to evolve or mentally train themselves efficiently if not for both wars specifically world war 1.