The document summarizes the imperialist activities of the United States in the late 1800s. It discusses how the U.S. gained control of Hawaii and influence in China and Japan through naval shows of force. It also covers the Spanish-American War, where the U.S. gained colonies like Puerto Rico and debated annexing the Philippines, and how President Theodore Roosevelt expanded U.S. influence in Latin America through policies like the Platt Amendment and Roosevelt Corollary.