Inter-American Treaty of Reciprocal Assistance

The Inter-American Treaty of Reciprocal Assistance, commonly called the Rio Treaty, is an intergovernmental collective security agreement the American states adopted on September 2, 1947 at a meeting in Rio de Janeiro, Brazil, and brought into force on December 3, 1948. Its central principle is that an attack against one signatory is to be treated as an attack against all of them. The treaty began with 23 signatories, and the Bahamas became the most recent country to join, signing and ratifying it in 1982, but several members have since breached or withdrawn from it: Bolivia, Ecuador, Nicaragua, and Venezuela withdrew between 2012 and 2014, Uruguay withdrew briefly in 2019 before reversing course the following year, and Cuba has been suspended from the treaty since 1962.