The North Atlantic Treaty Organization (NATO) is an alliance, or group of nations who work together, whose goal is to provide defense for all its members. The organization was founded in 1949. NATO's mission was spelled out in the North Atlantic Treaty, which stated that “an armed attack against one or more” of its members “shall be considered an attack against them all.” The alliance originally included the United States and several of its allies in western Europe, such as Great Britain and France.
NATO has its origins in the outcome of World War II. In that war, the United States, Great Britain, and the Soviet Union fought against and defeated Germany and Japan. After the war, the United States and the nations of western Europe reduced the sizes of their armies in Europe. Meanwhile, the Soviet Union continued to build its military, and it pulled together a number of eastern European countries as satellites, or nations that fell under the Soviet Union's political and military influence. By this time, cooperation between the western Allies and the Soviets had completely broken down. The tensions between the two groups led to a period known as the Cold War.
At the time, the United States was working with nations of western Europe to rebuild their economies and infrastructure. In addition, they soon began to discuss how to protect themselves against the growing power of the Soviet Union. These talks resulted in the signing of the North Atlantic Treaty in Washington, D.C., on April 4, 1949.
There were 12 original countries who signed the North Atlantic Treaty: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, The Netherlands, Norway, Portugal, the United Kingdom, and the United States. France withdrew its military support from NATO in 1966, because it did not want other nations to decide when it would go to war. However, France remained a non-military member. As a result of this change, the headquarters of NATO moved in 1966 from Paris to Brussels, Belgium, its current home. (France rejoined the military arm of NATO in 1995.)
Several other nations have joined NATO since its founding. Greece and Turkey joined in 1952, West Germany joined in 1955, and Spain joined in 1982. There was much debate over West Germany's joining so soon after World War II, but the size of the country was considered an effective defense against the Soviet Union.
The 1990s saw many changes in the membership of NATO as a result of the collapse of the Warsaw Pact, a military alliance between the Soviet Union and several eastern European nations. Hungary, Poland, and the Czech Republic—all former Soviet satellites—officially joined NATO in March 1999.
At a NATO summit in November 2002, seven other nations were invited into the alliance: Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia. These eastern European countries officially joined NATO in 2004.
A council in Brussels, known as the North Atlantic Council, governs the activity of NATO. Since 1966 this council has focused mostly on military matters. The council is broken down into a number of committees. The Military Committee of NATO has the highest military authority in the organization.
The military arm of NATO focuses on two main regions: Europe and the Atlantic. These two regions have separate military commands.
Despite the many wars in the second half of the 20th century, the military arm of NATO was not called upon until 1995. At that time the republics that had formerly made up Yugoslavia were engaged in fierce fighting, and NATO launched air strikes around the Bosnian capital of Sarajevo. NATO later set up peacekeeping troops in the area. NATO was once again called upon to launch air strikes against targets in the Balkan region in 1999. The later strikes were an effort to protect citizens of the province of Kosovo, in Serbia, from threats by the Serbian leader Slobodan Milosevic.
The shape of NATO changed greatly as a result of the breakdown of the Soviet Union in the early 1990s. In 1994 a program called Partnership for Peace was set up between NATO and non-NATO countries to conduct joint military training. Russia and Ukraine, the two largest nations among the former Soviet republics, played a large role in this partnership. The member nations of NATO even debated allowing Russia to join NATO.
In 1999 NATO celebrated its 50th anniversary in Washington, D.C., where the original treaty had been signed. At that summit, NATO enlarged its mission with a document known as the Strategic Concept. This expanded mission pointed to the combined threats of ethnic conflicts and human rights abuses in Europe and the Atlantic, and it affirmed NATO's readiness to control these crises, if necessary through the use of military force.
In the 20th century, despite the use of force in the Balkan wars, NATO did not use Article 5 of its treaty, which stated that an attack against one member was an attack against the alliance. The first time it did so was after September 11, 2001, when terrorists attacked targets in the United States, including the World Trade Center in New York City and the Pentagon in Washington, D.C. In October NATO sent troops and materials to aid the United States in its response to the attacks.
