The Monroe Doctrine is a US foreign policy principle asserting the United States' primacy in the Western Hemisphere. Introduced in President James Monroe's 1823 annual message to Congress and largely crafted by Secretary of State John Quincy Adams, it originally warned European powers against interfering in the Americas.
The doctrine was largely created in response to a wave of newly independent republics in Latin America, which the US sought to shield from recolonization by Spain and its European allies. Because the US lacked the military strength to back its own declaration, the British Royal Navy effectively upheld it for most of the 19th century, driven by its own interests in North and South America.
Over two centuries, presidents have expanded and reinterpreted the doctrine to fit the geopolitical context. Theodore Roosevelt used it to justify military interventions throughout Latin America, while Franklin Roosevelt later abandoned that approach with his Good Neighbor policy. During the Cold War, it was invoked to oppose Soviet influence in Cuba. In 2025, President Donald Trump announced a "Trump Corollary," vowing to reestablish US "dominance" across the hemisphere.
Hours of research by our editors, distilled into minutes of clarity.
Monroe outlined four positions: the US would not interfere in European conflicts; it would not disturb existing European colonies in the Americas; the Western Hemisphere was closed to new colonization; and any European attempt to control an independent American republic would be regarded as a threat to US security.
Between 1810 and 1822, many Latin American colonies separated from Spanish rule, 10 in the last two years. Concerns that Spain and its European allies might try to regain these republics were a main reason behind Monroe's declaration.
This podcast examines the Monroe Doctrine, from its casual origins in an 1823 congressional update to Trump's "Donroe Doctrine"—highlighting how fears of Chinese influence, concerns over oil prices, and the pursuit of hemispheric dominance influenced the administration's policies toward Latin America.
On Dec. 2, 1823, President Monroe delivered his seventh annual message to Congress, now known as the State of the Union. One segment—warning European powers against interfering in the Western Hemisphere—became known as the Monroe Doctrine.
Joel Roberts Poinsett, appointed as the first US minister to Mexico in 1825 following the doctrine's announcement, took cuttings of a vibrant Mexican plant called the cuetlaxochitl during his time there. Americans loved the foliage and named it after him.
Adams, the main foreign relations authority in the Cabinet, shaped the key parts of the Monroe Doctrine speech. He advocated for a unilateral American declaration to warn European powers, rejecting a potential joint statement with Britain favored by some Cabinet members.
This podcast explores the European background of the Monroe Doctrine, highlighting France's efforts to install aristocratic Bourbon monarchs in the newly independent Latin American republics—and how US opposition, British threats, and Spanish resistance ultimately disrupted those plans.
In the early to mid-1800s, the US lacked the ships and military power to prevent European nations from colonizing the Americas. Britain enforced this to protect its commercial interests by keeping rival European powers out of Latin America.
This podcast explores how the policy motivated a century of US military intervention throughout Latin America, the Caribbean, and the Pacific—covering the annexation of Hawaii, the Spanish-American War, and occupations of Cuba, Haiti, and Panama.
In 1904, President Theodore Roosevelt declared that the US had the right to exercise international police power in Latin America. Over the following two decades, the US intervened militarily in the region about a dozen times—often enough that Marines became known locally as "State Department troops."
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