Glossary: Rio Treaty (Inter-American Treaty of Reciprocal Assistance)
DEFINITION:
A regional alliance, signed in Rio de Janeiro in 1947, that established a mutual security system to safeguard the Western Hemisphere from aggression from within or outside the zone. Signatories include the United States and twenty Latin American republics. In 1975 a special conference approved, over United States objections, a Protocol of Amendment to the Rio Treaty that, once ratified, would establish the principle of ""ideological pluralism"" and would simplify the rescinding of sanctions imposed on an aggressor party.