Monroe Doctrine

Declaration by US president James Monroe in 1823 that the USA would not tolerate any European nation trying to establish a colony in the Americas, and that any attempt to do so would be regarded as a threat to US peace and security. At the time, several European countries were proposing to intervene in former Spanish and Portuguese colonies in Latin and South America, and Russia was attempting to extend its Alaskan territories into Oregon country. In return for the cessation of such European ambitions, the USA would not interfere in European affairs. The doctrine, subsequently broadened, has been a recurrent theme in US foreign policy, although it has no basis in US or international law.

At the time of the declaration, the USA was militarily incapable of enforcing it, but they were encouraged and supported by the British, whose commercial interests were at risk. The Monroe Doctrine was cited a number of times in the 19th century; for example, against France in 1865 (who had backed the Confederacy during the American Civil War), and during a border dispute between Venezuela and Britain in 1895. In the early 20th century, President Theodore Roosevelt used it to proclaim a US right to intervene in the internal affairs of Latin American states. The doctrine also contributed to the USA's building of the Panama Canal (1904–14), and played a part in the Cuban missile crisis (1962), a confrontation with the USSR over Soviet missile bases established in Cuba).