Monroe Doctrine: A principle of US policy, originated by President James Monroe in 1823, that any intervention by external powers in the politics of the Americas is a potentially hostile act against the US.
Roosevelt Corollary: An addition to the Monroe Doctrine articulated by President Theodore Roosevelt asserting that the U.S. might intervene in the domestic affairs of Western Hemisphere nations to maintain stability.
Pan-Americanism: A movement that seeks to create, encourage, and organize relationships, associations and cooperation among states within the Americas.