A historical analysis of NATO strategic concepts in the context of regional and global security threats

The USSR's very rapid political and military growth after the Second World War and its attempt to extend its sphere of influence to the spheres of influence of the US and the national borders of Western European countries led to serious chaos in the international system. The international system entered into a division in military, political, and economic terms, with the USA and the USSR being in the center. NATO, a military alliance, was established by Western European states under the leadership of the United States as an element of balance against the USSR during the Cold War. Since European states did not have the military or financial capacity to ensure their own security at that time, they supported the establishment of NATO. Although NATO served as a security umbrella for European states, it prioritized the important task of protecting the economic and political interests of the United States, especially in Europe. NATO, which emerged in the international arena after the Cold War and still continues its formation process today, has become more complex with the actor states included in it, and the strategies followed by these actors according to their weight have changed and matured over time. In the post-Cold War era, European allies declared that NATO was no longer needed. In this context, the aim of this thesis is to analyze how and for what reasons NATO can continue its existence although the Cold War period has ended. The main argument of the thesis is that NATO continues to exist in the post-Cold War period while consolidating its legitimacy by undertaking new missions in the face of regional and global threats. In this context, energy security, cyber security, weapons of mass destruction, the Russian-Ukrainian War, the fight against international terrorism, and Afghanistan as an area of activity beyond the mission of NATO stand out as new security threats and challenges