The primary purpose of the US Monroe Doctrine, articulated in 1823, was to assert that European colonialism in the Americas was no longer acceptable. It warned European nations against further colonization or intervention in the Western Hemisphere, positioning the United States as the dominant power in the region. The Doctrine was motivated by the desire to protect newly independent Latin American countries from European influence and was rooted in a belief in self-determination. While the effectiveness of the Monroe Doctrine has been debated, it established a crucial precedent for US foreign policy and interventions in the Americas.