Final answer:
The shift in American attitudes toward gaining imperial territories was largely due to economic incentives and access to new markets, driven by the industrial boom and the economic depression of the 1890s.
Step-by-step explanation:
Throughout the late 19th century, the United States experienced a shift in foreign policy from a nation that largely adhered to George Washington's advice of avoiding entanglements in foreign affairs to one that actively sought imperial territories.
This change was primarily driven by economic incentives and access to new markets. The industrial boom in the U.S. created a need to expand overseas to sell products and obtain raw materials. The economic depression of the 1890s amplified these needs, leading business owners and politicians to support imperialism as a means to open up new markets.