ID: Monroe Doctrine

When: December 2, 1823

President James Monroe (The doctrine was written by Secretary of State John Quincy Adams, but it was part of Monroe’s annual message to Congress)

A foreign policy statement declaring that:

The Americas were closed to further European colonization. Any attempts to colonize or interfere in the Western Hemisphere by European powers would be considered a hostile act against the United States.
The United States would not interfere in the internal affairs of European nations or their existing colonies.
The United States recognized and would not interfere with existing colonies in the Western Hemisphere.

Established the U.S. as a dominant power in the Western Hemisphere.
Asserted American neutrality in European conflicts, signaling a departure from its previous involvement in European affairs.
Laid the groundwork for future U.S. interventionism in Latin America. While initially about protecting the Americas from Europe, the Monroe Doctrine would later be used to justify U.S. interventions in Latin American countries.
Had little impact at the time as the U.S. lacked the military strength to enforce it. Its significance grew later in the 19th century as the U.S. became a stronger nation.
Remains a cornerstone of U.S. foreign policy today, though its interpretation and application have evolved over time.