December 2, 1823: James Monroe issues the Monroe Doctrine.
Since its introduction during the so-called “Era of Good Feelings”, the Monroe Doctrine has remained an essentially unchanging part of the United States’ foreign policy. It was conceived by a United States that feared the restored and allied monarchies of post-Napoleon Europe would attempt to establish colonies or spheres of influence in the New World. As a result, James Monroe established his namesake doctrine at his seventh State of the Union Address, which stated that
…the American continents, by the free and independent condition which they have assumed and maintain, are henceforth not to be considered as subjects for future colonization by any European powers.
In short, the doctrine declared that any attempts by European powers to take over New World territories would be seen by the United States as an act of hostility (although existing colonies would be tolerated). The United States, not yet a world power, had not the military power nor the global influence to issue such a bold statement to the European powers, but it was mostly enforced by the British navy, which laid the foundation for the two nations’ “Special Relationship”.
The Monroe Doctrine was significantly applied several times throughout U.S. history. At face value it seemed to be a decrial of colonialism, and the United States did raise objections to some European actions on the grounds of the doctrine’s principles - in 1862, France’s invasion of Mexico was deemed to be a violation of the doctrine, for example. Criticism for the doctrine comes mostly for its later use as a tool for establishing American hegemony in the Western Hemisphere; rather than defending the Americas from European domination, it would simply replace a European oppressor with an American one. In 1845, it was used as justification for the United States’ acquisition of Texas in pursuit of “Manifest Destiny”. In 1904 Theodore Roosevelt added the Roosevelt Corollary; by this time the United States was an emerging world power, so it now had the strength to support this new corollary. It declared that the country had the right to intervene in Latin America to stave off European influence, leading some to criticize the United States’ subsequent role as “hemispheric policeman.” The Monroe Doctrine was also invoked several times during the Cold War, this time against the spread of communism.