What did the Monroe Doctrine assert?

The Monroe Doctrine asserted that the Western Hemisphere was off-limits to European intervention, which articulated a significant shift in American foreign policy. Formulated in 1823 by President James Monroe, this doctrine was intended to prevent further European colonization and asserted that any attempt by Europe to interfere in the politics of the Americas would be viewed as a hostile act against the United States.

The emphasis on non-intervention was a response to European powers' expansionist ambitions in the region, particularly in light of various colonies and newly independent nations in Latin America. By declaring the Americas as a zone free from European exploitation, the Monroe Doctrine not only aimed to protect the sovereignty of Latin American countries but also positioned the United States as the dominant power in the Western Hemisphere.

Meanwhile, claims of encouraging European colonization or involving the U.S. in European affairs do not align with the essence of the Monroe Doctrine. Additionally, while the U.S. did promote democracy in various contexts, that was not the primary assertion of the doctrine itself. Therefore, the key assertion of the Monroe Doctrine is that it firmly established the Western Hemisphere as a sphere of U.S. influence, effectively discouraging European interference.