An imperialistic agenda refers to a set of policies and actions aimed at extending a nation's power and influence over other territories, often through colonization, military conquest, or economic dominance. This agenda can manifest in various forms, such as the desire for new markets, strategic territories, or resources. It played a crucial role in shaping U.S. foreign policy during significant events like the Spanish-American War, where the U.S. sought to expand its territorial reach and influence in the Caribbean and the Pacific.