Answer:
Japan's imperialism had a significant impact on the United States. Japan's militaristic expansion into East Asia during the late 19th and early 20th centuries led to increased tension between the two countries. This tension ultimately led to the attack on Pearl Harbor in 1941, which catalyzed the United States' entry into World War II. The war effort necessitated the mobilization of troops and resources and resulted in an unprecedented level of economic growth, technological advancement, and social change. Japan's imperialism also had a lasting effect on the United States' presence in East Asia, which has continued to shape the region's politics and culture to this day.