The document discusses U.S. expansion and imperialism from 1867 to 1905. It outlines the intellectual and strategic motivations for expansion, including the Monroe Doctrine and ideas of Manifest Destiny. Key events discussed include the purchase of Alaska, annexation of Hawaii, the Spanish-American War over Cuba, the Philippine Insurrection, and increased U.S. interventions in Latin America through policies like the Platt Amendment and the creation of the Panama Canal.