The Act of Chapultepec was approved in 1945 at the Chapultepec Conference, which was an Inter-American conference held in Mexico City. The act was adopted by 20 countries resolved to take action in repelling any aggression against an American state. This was finalized by the Inter-American Treaty of Reciprocal Assistance (the Rio Treaty of 1947), and constituted an important step in the history of Pan-Americanism. The acceptance of the act by Argentina established machinery to enforce peace in the Western Hemisphere. The act basically said that the countries of the Western Hemisphere were to act collectively in their own defense unless and until the World Security Council (WSC) should take effective measures to deal with an attack.
RECIPROCAL ASSISTANCE AND AMERICAN SOLIDARITY
WHEREAS:
The peoples of the Americas, animated by a profound love of justice, remain sincerely devoted to the principles of international law;
It is their desire that such principles, notwithstanding the present difficult circumstances, prevail with even greater force in future international relations;
The inter-American conferences have repeatedly proclaimed certain fundamental principles, but these must be reaffirmed at a time when the juridical bases of the community of nations are being re-established;
The new situation in the world makes more imperative than ever the union and solidarity of the American peoples, for the defense of their rights and the maintenance of international peace;
The American states have been incorporating in their international law, since 1890, by means of conventions, resolutions and declarations, the following principles:
a) The proscription of territorial conquest and the non-recognition of all acquisitions made by force (First International Conference of American States, 1890);
b) The condemnation of intervention by one State in the internal or external affairs of another (Seventh International Conference of American; States, 1933, and Inter-American Conference for the Maintenance of Peace, 1936;
c ) The recognition that every war or threat of war affects directly or indirectly all civilized peoples, and endangers the great principles of liberty and justice which constitute the American ideal and the standard of American international policy Inter-American Conference for the Maintenance of Peace, 1936);
d) The system of mutual consultation in order to find means of peaceful cooperation in the event of war or threat of war between American countries (Inter-American Conference for the Maintenance of Peace, 1936);
e) The recognition that every act susceptible of disturbing the peace of America affects each and every one of the American nations and justifies the initiation of the procedure of consultation (Inter-American Conference for: the Maintenance of Peace, 1936);
f ) The adoption of conciliation, unrestricted arbitration, or the application of international justice, in the solution of any difference or dispute between American nations, whatever its nature or origin ( Inter-American Conference for the Maintenance of Peace, 1936);
g) The recognition that respect for the personality, sovereignty and independence of each American State constitutes the essence of international order sustained by continental solidarity, which historically has been expressed and sustained by declarations and treaties in force (Eighth International Conference of American States, 1938);
h) The affirmation that respect for and the faithful observance of treaties constitute the indispensable rule for the development of peaceful relations between States, and that treaties can only be revised by agreement of the contracting parties (Declaration of American Principles, Eighth International Conference of American States, 1938);
i) The proclamation that, in case the peace, security or territorial integrity of any American republic is threatened by acts of any nature that may impair them, they proclaim their common concern and their determination to make effective their solidarity, coordinating their respective sovereign wills by means of the procedure of consultation, using the measures which in each case the circumstances may make advisable (Declaration of Lima, Eighth International Conference of American States, 1938);
j ) The declaration that any attempt on the part of a non-American state against the integrity or inviolability of the territory, the sovereignty or the political independence of an American State shall be considered as an act of aggression against all the American States (Declaration XV of the Second Meeting of the Ministers of Foreign Affairs, Habana, 1940);
The furtherance of these principles, which the American States have constantly practiced in order to assure peace and solidarity among the nations of the Continent, constitutes an effective means of contributing to the general system of world security and of facilitating its establishment;
The security and solidarity of the Continent are affected to the same extent by an act of aggression against any of the American States by a non-American State, as by an act of aggression of an American State against one or more American States;
PART I
The Governments Represented at the Inter-American Conference on Problems of War and Peace
DECLARE:
1. That all sovereign States are juridically equal among themselves.
2. That every State has the right to the respect of its individuality and independence, on the part of the other members of the international community.
3. That every attack of a State against the integrity or the inviolability of the territory, or against the sovereignty or political independence of an American State, shall, conformably to Part III hereof, be considered as an act of aggression against the other States which sign this Act. In any case invasion by armed forces of one State into the territory of another trespassing boundaries established by treaty and demarcated in accordance therewith shall constitute an act of aggression.
4. That in case acts of aggression occur or there are reasons to believe that an aggression is being prepared by any other State against the integrity or inviolability of the territory, or against the sovereignty or political independence of an American State, the States signatory to this Act will consult among themselves in order to agree upon the measures it may be advisable to take.
5. That during the war, and until the treaty recommended in Part II hereof is concluded, the signatories of this Act recognize that such threats and acts of aggression, as indicated in paragraphs 3 and 4 above, constitute an interference with the war effort of the United Nations, calling for such procedures, within the scope of their constitutional powers of a general nature and for war, as may be found necessary, including: recall of chiefs of diplomatic missions; breaking of diplomatic relations; breaking of consular relations; breaking of postal, telegraphic, telephonic, radio-telephonic relations; interruption of economic, commercial and financial relations; use of armed force to prevent or repel aggression.
6. That the principles and procedure contained in this Declaration shall become effective immediately, inasmuch as any act of aggression or threat of aggression during the present state of war interferes with the war effort of the United Nations to obtain victory. Henceforth, and to the end that the principles and procedures herein stipulated shall conform with the constitutional processes of each Republic, the respective Governments shall take the necessary steps to perfect this instrument in order that it shall be in force at all times.
PART II
The Inter-American Conference on Problems of War and Peace
RECOMMENDS:
That for the purpose of meeting threats or acts of aggression against any American Republic following the establishment of peace, the Governments of the American Republics consider the conclusion, in accordance with their constitutional processes, of a treaty establishing procedures whereby such threats or acts may be met by the use, by all or some of the signatories of said treaty, of any one or more of the following measures: recall of chiefs of diplomatic missions; breaking of diplomatic relations; breaking of consular relations; breaking of postal, telegraphic, telephonic, radio-telephonic relations; interruption of economic, commercial and financial relations; use of armed force to prevent or repel aggression.
PART III
The above Declaration and Recommendation constitute a regional arrangement for dealing with such matters relating to the maintenance of international peace and security as are appropriate for regional action in this Hemisphere. The said arrangement, and the pertinent activities and procedures, shall be consistent with the purposes and principles of the general international organization, when established.
This agreement shall be known as the "Act of Chapultepec."
{The final act of the Inter-American Conference on Problems of War and Peace was signed on March 8, 1945, by delegates representing Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, the Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, the United States, Uruguay, and Venezuela.}