# Monroe Doctrine **Domain:** U.S. Foreign Policy / Hemispheric Strategy / History **Doc Type:** Doctrine Node **Maturity:** Developing **Concept Hub:** [[wiki/War With Empire|War With Empire]] ## Definition **The Monroe Doctrine is the U.S. policy announced by President James Monroe in his annual message to Congress on December 2, 1823, declaring the Western Hemisphere closed to further European colonization and treating European intervention in the Americas as a threat to the United States.** Secretary of State John Quincy Adams shaped the policy and insisted that it be issued unilaterally rather than as a joint declaration with Britain, as Foreign Secretary George Canning had proposed. ## Later Forms The Roosevelt Corollary (1904) asserted a U.S. right to intervene in the hemisphere. In 2025–2026 the Trump administration revived the doctrine as the "Trump Corollary," and Trump named its expanded form the [[wiki/Don-roe Doctrine|Don-roe Doctrine]] after the January 2026 capture of Nicolás Maduro. ## War With Empire Context [[articles/war with empire/The Monroe Doctrine, the British Substrate, and the Unfinished Decolonization of the Americas|The Monroe Doctrine, the British Substrate, and the Unfinished Decolonization of the Americas]] treats the doctrine as an authorship dispute and an unfinished decolonization project whose nineteenth-century enforcement rested on British naval power, an instance of [[wiki/Declarative Sovereignty|declarative sovereignty]] resting on another power's substrate. [[articles/war with empire/Greenland and Freedom City|Greenland and Freedom City]] reads the [[wiki/2026 Greenland Security Agreement|2026 Greenland Security Agreement]] as the doctrine's northern completion. ## Key Insight **A doctrine is sovereign only when the substrate enforcing it is one's own.** ## See Also [[wiki/Functional Decolonization|Functional Decolonization]] · [[wiki/Practical Sovereignty|Practical Sovereignty]] · [[wiki/Falkland Islands|Falkland Islands]] ## Relationships - **Revised as:** [[wiki/Don-roe Doctrine|Don-roe Doctrine]]. - **Source articles:** [[articles/war with empire/The Monroe Doctrine, the British Substrate, and the Unfinished Decolonization of the Americas|The Monroe Doctrine, the British Substrate, and the Unfinished Decolonization of the Americas]] · [[articles/war with empire/Greenland and Freedom City|Greenland and Freedom City]] in [[collections/War With Empire|War With Empire]]. ## Sources / Provenance - [Monroe Doctrine, 1823](https://history.state.gov/milestones/1801-1829/monroe) (U.S. Department of State, Office of the Historian).