NATO: History, Structure, Collective Defence, Recent Summits and Comparison with Other Security Organizations

The North Atlantic Treaty Organization, commonly known as NATO, is a political and military alliance established in 1949 to protect its members through collective defence. Its central principle is contained in Article 5 of the North Atlantic Treaty: an armed attack against one member is treated as an attack against all members. NATO currently consists of 32 countries from Europe and North America. Its responsibilities have expanded from Cold War defence to crisis management, counter terrorism, cyber defence, space security, military cooperation, protection of critical infrastructure and support for partner countries. The most recent NATO Summit was held in Ankara, Türkiye, on 7–8 July 2026.