https://en.m.wikipedia.org/wiki/Inter-American_Treaty_of_Reciprocal_Assistance

The Inter-American Treaty of Reciprocal Assistance (commonly known as the Rio Treaty, the Rio Pact, the Treaty of Reciprocal Assistance, or by the Spanish-language acronym TIAR from Tratado Interamericano de Asistencia Recíproca) is an agreement signed in 1947 in Rio de Janeiro among many countries of the Americas.[2] The central principle contained in its articles is that an attack against one is to be considered an attack against them all; this was known as the "hemispheric defense" doctrine. Despite this, several members have breached the treaty on multiple occasions. The treaty was initially created in 1947 and came into force in 1948, in accordance with Article 22 of the treaty. The Bahamas was the most recent country to sign and ratify it in 1982.[1]

https://en.m.wikipedia.org/wiki/Monroe_Doctrine

The Monroe Doctrine is a United States foreign policy position that opposes European colonialism in the Western Hemisphere. It holds that any intervention in the political affairs of the Americas by foreign powers is a potentially hostile act against the United States.[1] The doctrine was central to American grand strategy in the 20th century.[2]

The Organization of American States (OAS or OEA; Spanish: Organización de los Estados Americanos; Portuguese: Organização dos Estados Americanos; French: Organisation des États américains) is an international organization founded on 30 April 1948 to promote cooperation among its member states within the Americas.

https://en.m.wikipedia.org/wiki/Organization_of_American_States