What was the Monroe Doctrine?

The Monroe Doctrine was a significant U.S. policy established in 1823 that opposed European colonialism in the Americas. It articulated a clear stance that any further intervention by European nations in the affairs of countries in the Western Hemisphere would be viewed as acts of aggression, which the United States would counter. This policy was rooted in the belief that the newly independent nations of Latin America should be free from European influence and control, reflecting the United States' desire to expand its influence to safeguard its interests.

By asserting this position, the Monroe Doctrine sought to establish a clear line of demarcation between the Old World (Europe) and the New World (the Americas), emphasizing that the Americas were no longer a place for European expansionist ambitions. The doctrine served as a foundational component of American foreign policy and can be seen as an early expression of American imperialism, although it proclaimed a protective stance rather than an imperial one. This context makes it clear why the answer regarding opposing European colonialism in the Americas is accurate.