How did Manifest Destiny influence U.S. expansion in the 19th century, and how does it compare to later imperialism?

• A. Justified westward expansion; later imperialism extended influence abroad through acquisitions/colonialism
• B. Noninterventionist policies
• C. Isolationism
• D. Economic protectionism

Answer: (A)

Manifest Destiny captures the unfoldment of expansion as a national mission. It framed the United States as destined to spread democracy, liberty, and American institutions across the continent, which helped drive westward settlement and the acquisition of vast tracts of land—think of the annexation of Texas, the Oregon path to settlement, and the Mexican-American War that produced the Mexican Cession, eventually bringing California and much of the Southwest into the United States. This era created a more connected and cohesive continental nation through territorial growth absorbed into American governance.

Later imperialism shows a continuation of the same impulse to expand influence, but on a global scale. Instead of settling lands within a continental border, the United States extended power overseas through acquisitions and colonial arrangements—territories like Puerto Rico, Guam, and the Philippines, as well as strategic holdings and influence in places such as Hawaii and parts of China. The underlying idea—expanding American influence to secure economic and strategic interests—continues, but the methods shift from settling and organizing new lands within the continent to governing distant territories and projecting power abroad.

Choices that describe noninterventionist policies, isolationism, or economic protectionism don’t fit this pattern, as Manifest Destiny and subsequent imperialism were about outward expansion and influence rather than staying apart from global affairs or merely protecting domestic markets.