Final answer:
American imperialism was advocated by the United States as a policy due to the desire for political, economic, and military control over other nations, influenced by the observation of European empires. This shift away from Washington's advice is evident in the document.
Step-by-step explanation:
The document suggests that American imperialism was advocated as a policy of the United States due to the country's desire to expand its political, economic, and military control over other nations. This was driven by the observation of great empires in Europe that were acquiring territories in Africa, Asia, and the Pacific. The document highlights how the allure of empire became irresistible for the United States, leading to a shift away from Washington's advice of avoiding overseas relationships.