Final answer:
At the turn of the 20th century, American attitudes shifted from isolationism to imperialism, compelled by economic motives, strategic competition, and ideologies like an adapted form of Manifest Destiny.
Step-by-step explanation:
At the turn of the 20th century, the American mindset toward expansionism changed significantly, moving away from isolationism towards an expansion-mindedness and imperialism. Throughout the last decades of the 19th century, technological advancements, the pursuit of new markets and raw materials, the competition with European empires, and the belief in a 'civilizing mission' led the United States to expand its influence overseas. The 1890s marked a critical turning point where the United States began to shift towards this expansionism, influenced by ideologies such as Manifest Destiny that were adapted to justify new overseas conquests.
The late 19th century saw America's interest in overseas expansion fueled by various factors, including competition with European nations, desire for economic growth, and a sense of national destiny or Manifest Destiny, which earlier had been to expand across the North American continent. This new imperialism was characterized by a scramble, akin to Europe's 'Scramble for Africa', for colonies and spheres of influence in regions like the Caribbean, Pacific, and later, the Philippines, following the Spanish-American War.
The impact of this transition from isolationism to a proactive imperialistic approach was profound, setting the stage for the United States to emerge as a global power. Historians continue to debate whether this shift toward empire-building was a deliberate strategy or a consequence of America's growing power and interests. Nonetheless, American expansionism at the turn of the 20th century represents a crucial chapter in its history, as the nation sought a role on the international stage that echoed the imperial pursuits of other great powers of the time.