The Monroe Doctrine was a foreign policy statement issued by President James Monroe in 1823. It declared that any European colonization or intervention in the Americas would be considered an act of aggression towards the United States and that the U.S. would not interfere in European affairs.
Related terms
Manifest Destiny: The belief held by many Americans in the 19th century that it was their destiny to expand across the continent from coast to coast.
Isolationism: An approach to foreign policy that seeks to avoid involvement in international conflicts or alliances.
Gunboat Diplomacy: The use of military force or threats of force to achieve diplomatic objectives during international negotiations.