World military alliances: which countries have agreed to protect each other?
Visual Capitalist has mapped five of the world's multilateral defense structures and agreements. Among them are the 32-member NATO, the Rio Pact, the CSTO, the Cooperation Council for the Arab States of the Gulf, and the new Mecca Agreement signed by Saudi Arabia, Turkey, and Pakistan.
World military alliances: which countries have agreed to defend each other?
The map highlights official multilateral agreements that entail mutual defense obligations. General military cooperation or partnerships in the field of defense technologies are considered as a separate category.
The main principle of such agreements is that an armed attack against one of the participants is considered an attack against all. However, the procedure for providing assistance and the specific obligations of the parties are defined separately in each treaty.
Among the presented associations, NATO is the largest in terms of the number of members. Established in 1949 by 12 countries, the alliance now unites 32 countries in Europe and North America. Finland joined it in 2023, and Sweden in 2024.
The oldest agreement on the map is the Inter-American Treaty of Reciprocal Assistance, known as the Rio Pact. It was signed in 1947, two years before NATO.
The Rio Pact formed a collective defense system in the Western Hemisphere. In the following decades, the composition of its participants has changed. The US is a member of both the Rio Pact and NATO.
The Cooperation Council for the Arab States of the Gulf unites six monarchies in the region. Saudi Arabia is also part of this structure.
In August 2026, Saudi Arabia, Turkey, and Pakistan signed the Mecca Joint Defense Agreement. According to the document, an armed attack against one of the three countries is considered an attack against all.
However, the signing of the agreement is not the same stage as its full entry into force. According to Reuters on September 25, the Speaker of the Turkish Parliament, Numan Kurtulmuş, said that the submission of the document for parliamentary approval is expected from October. He described the meetings held so far as a preparatory process.
Turkey is a member of NATO, and Saudi Arabia is a member of the Cooperation Council for the Arab States of the Gulf. Pakistan does not belong to these two structures and is a nuclear-armed state. In this sense, the new agreement creates an additional link between different regional security systems.