NATO is a military alliance between nations, and now includes 28 states. The original goal of this alliance, established by the United States in April of 1949, was to ensure the safety of the United States from an attack by countries in the Soviet bloc. With the start of military tensions between the United States and the Soviet Union, known as the Cold War, communist countries joined forces in the Warsaw Pact, the Soviet reaction to NATO. With the collapse of the Soviet Union between 1989 and 1991, NATO lost its original purpose as a defensive body against a Russian attack and instead refocused itself as an armed peacekeeping force, as evidenced by the 1992 intervention in the former Yugoslavia. In recent years, the alliance has expanded to include Eastern European countries, including 12 countries formerly under Soviet influence. Following the terrorist attacks September 11th 2001, the U.N. activated Article 5 of its charter for the first time. This article states that an armed attack against a member country must be considered an attack against all the countries participating in the Treaty. For this reason, NATO countries decided to invade Afghanistan with the support of the UN.

NATO has its headquarters in Brussels, Belgium. The Secretary-General and the commander are its two main leaders. They’re elected in turns between the various Member States and meet at least twice a year to discuss the strategy of action. NATO military forces are stationed in several bases throughout Europe and the world and are comprised of the armies from various countries, with the U.S. having a dominant presence. A holdover from the Cold War, nuclear arsenals located at some NATO bases have led to clashes between the military and the local population of those countries. The actual number of these weapons is a military secret. During the Cold War, NATO’s activities proved effective against a Soviet threat. The role NATO, in collaboration with the UN, has played since 1992 has been even more important in maintaining peace and order, such as in the former Yugoslavia or Afghanistan