Collective security is one of the most promising approaches to peace and a valuable tool for energy management at the international level. In 1629, Cardinal Richelieu proposed a system of collective security that was partly reflected in the peace of Westphalia of 1648. In the 18th century, many proposals for collective security measures were made, particularly in Europe. In 1952, the members agreed on the accession of Greece and Turkey to NATO and added the Federal Republic of Germany in 1955. The accession of West Germany prompted the Soviet Union to take retaliatory measures with its own regional alliance, which took the form of the Warsaw Treaty organization and was part of the Soviet satellite states of Eastern Europe. Since its inception, the accession of new Member States has increased the alliance from 12 to 30 countries. The youngest member state added to NATO was Northern Macedonia on 27 March 2020. These extensive negotiations led to the signing of the North Atlantic Treaty in 1949. In this agreement, the United States, Canada, Belgium, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal and the United Kingdom agreed to consider an attack on all and consultations on threats and defence issues. This collective defence agreement formally applied only to attacks on signatories in Europe or North America; Conflicts in colonial areas were not included. After the signing of the treaty, some signatories requested U.S. military assistance.
Later in 1949, President Truman proposed a military assistance program, and the Mutual Defense Assistance Program passed the U.S. Congress in October, with about $1.4 billion for the construction of Western European defense equipment. All NATO organizations and organizations are integrated into either the civilian administrative or military executive. For the most part, they perform roles and functions that directly or indirectly support the Alliance`s security role. International cooperation for the promotion of collective security was born in the concert of Europe that developed after the Napoleonic wars of the 19th century to maintain the status quo between European states and thus avoid a war.  It was also at this time that international law was developed with the first Geneva Conventions establishing laws on humanitarian aid during the war and the international conventions of The Hague of 1899 and 1907 on the rules of war and the peaceful settlement of international disputes.   Alliance, in international relations, a formal agreement between two or more states for mutual assistance in the event of war.