Table of Contents
Table of Contents
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Have two NATO countries ever gone to war against each other?
No. Two disputes over fisheries, the “Cod Wars” (1958–1976, between Iceland and the United Kingdom) and the “Turbot Wars” (1995, between Canada and Spain), were resolved bloodlessly, although Iceland did threaten to withdraw from NATO over the matter. The closest that two NATO members have come to open hostilities was in Cyprus in 1974. After Greece’s military junta backed a coup in Cyprus—the goal of which was to achieve enosis (union between Greece and Cyprus)—Turkish troops landed and eventually occupied the northern third of the island. Open war between Greece and Turkey was avoided in part because the Greek junta’s attempt to mobilize was so disastrous and domestically unpopular that it led to the collapse of the military government and the restoration of democracy in Athens.
Can the president pull the U.S. out of NATO?
No. Section 1250A of the National Defense Authorization Act for Fiscal Year 2024 explicitly states: “The President shall not suspend, terminate, denounce, or withdraw the United States from the North Atlantic Treaty, done at Washington, DC, April 4, 1949, except by and with the advice and consent of the Senate, provided that two-thirds of the Senators present concur, or pursuant to an Act of Congress.” This act easily passed both the House and Senate with wide bipartisan support.
Who has the largest army in NATO?
The United States has the largest army in NATO, with about 1.3 million personnel. Next on the list is Turkey with almost 450,000. The rest of the top five are France (200,000), Germany (180,000), and Italy (175,000). (Numbers are approximate.)
What is NATO’s Article 4?
Article 4 of the North Atlantic Treaty states: “The Parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened.” The invocation of Article 4 is not a prerequisite to Article 5, the pledge of collective defense that serves as the heart of the treaty, nor is it a guarantee that Article 5 will be activated. Poland invoked Article 4 on September 10, 2025, after a wave of Russian drones violated Polish airspace and NATO fighter jets shot a number of them down.
When did the U.S. join NATO?
The United States joined NATO in 1949 as one of the 12 founding members. The others are Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, and the United Kingdom.
What is the purpose of NATO?
The purpose of NATO is to “to safeguard the freedom and security of all its members. It does this through political and military means.” The heart of NATO is expressed in Article 5 of the North Atlantic Treaty, in which the signatory members agree that: “an armed attack against one or more of them in Europe or North America shall be considered an attack against them all.” The alliance currently has 32 member countries.
Has NATO’s Article 5 ever been invoked?
NATO’s Article 5 is central to the alliance. The signatory members agree that “an armed attack against one or more of them in Europe or North America shall be considered an attack against them all.” The article has only been invoked one time: in 2001, after the September 11 attacks organized by Osama bin Laden destroyed the World Trade Center in New York City and part of the Pentagon outside Washington, D.C., killing some 3,000 people.
How many countries are in NATO?
Currently 32 countries are members of NATO: Albania, Belgium, Bulgaria, Canada, Croatia, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Montenegro, the Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Turkey, the United Kingdom, and the United States.
What does NATO stand for?
NATO is an acronym for North Atlantic Treaty Organization.
The North Atlantic Treaty Organization (NATO) is a military alliance originally established in 1949 to create a counterweight to Soviet armies stationed in central and eastern Europe after World War II. When the Cold War ended, NATO was reconceived as a “cooperative-security” organization.
Which countries are in NATO?
The 32 current member states of NATO are Albania, Belgium, Bulgaria, Canada, Croatia, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Montenegro, the Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Turkey, the United Kingdom, and the United States.
What are the newest members of NATO?
Sweden is the newest member of NATO. It joined the alliance as its 32nd member in March 2024. Sweden announced its intention to join NATO in 2022, in response to Russia’s invasion of Ukraine, but its membership bid was held up for two years by objections from Turkey and Hungary.
Finland joined NATO in April 2023, also in response to Russia’s invasion of Ukraine.
North Atlantic Treaty Organization (NATO), military alliance established in 1949 that sought to create a counterweight to Soviet armies stationed in central and eastern Europe after World War II. Following the end of the Cold War, NATO was reconceived as a “cooperative-security” organization. It has 32 member states.
The heart of NATO is expressed in Article 5 of the North Atlantic Treaty (also called the Washington Treaty), which founded the alliance on April 4, 1949. In Article 5, the signatory members agree that
an armed attack against one or more of them in Europe or North America shall be considered an attack against them all; and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defense recognized by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.
NATO invoked Article 5 for the first time in 2001, after the September 11 attacks organized by Osama bin Laden destroyed the World Trade Center in New York City and part of the Pentagon outside Washington, D.C., killing some 3,000 people.
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Article 6 defines the geographic scope of the treaty as covering “an armed attack on the territory of any of the Parties in Europe or North America.” Other articles commit the allies to strengthening their democratic institutions, to building their collective military capability, to consulting each other, and to remaining open to inviting other European states to join.
NATO’s original members in 1949 were Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom, and the United States.
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The countries that joined NATO after its founding are Greece and Turkey (1952); West Germany (1955; from 1990 as Germany); Spain (1982); the Czech Republic, Hungary, and Poland (1999); Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, and Slovenia (2004); Albania and Croatia (2009); Montenegro (2017); North Macedonia (2020); Finland (2023); and Sweden (2024).
France withdrew from the integrated military command of NATO in 1966 but remained a member of the organization; it resumed its position in NATO’s military command in 2009.
Historical background North Atlantic TreatyU.S. Secretary of State Dean Acheson signing the North Atlantic Treaty on April 4, 1949, as U.S. Pres. Harry S. Truman (second from left) and Vice Pres. Alben W. Barkley (left) look on.(more)
After World War II in 1945, western Europe was economically exhausted and militarily weak (the western Allies had rapidly and drastically reduced their armies at the end of the war), and newly powerful communist parties had arisen in France and Italy. By contrast, the Soviet Union had emerged from the war with its armies dominating all the states of central and eastern Europe, and by 1948 communists under Moscow’s sponsorship had consolidated their control of the governments of those countries and suppressed all noncommunist political activity. What became known as the Iron Curtain, a term popularized by Winston Churchill, had descended over central and eastern Europe. Further, wartime cooperation between the western Allies and the Soviets had completely broken down. Each side was organizing its own sector of occupied Germany, so that two German states would emerge, a democratic one in the west and a communist one in the east.
In 1948 the United States launched the Marshall Plan, which infused massive amounts of economic aid to the countries of western and southern Europe on the condition that they cooperate with each other and engage in joint planning to hasten their mutual recovery. As for military recovery, under the Brussels Treaty of 1948, the United Kingdom, France, and the Low Countries—Belgium, the Netherlands, and Luxembourg—concluded a collective-defense agreement called the Western European Union. It was soon recognized, however, that a more formidable alliance would be required to provide an adequate military counterweight to the Soviets.
By this time Britain, Canada, and the United States had already engaged in secret exploratory talks on security arrangements that would serve as an alternative to the United Nations (UN), which was becoming paralyzed by the rapidly emerging Cold War. In March 1948, following a virtual communist coup d’état in Czechoslovakia in February, the three governments began discussions on a multilateral collective-defense scheme that would enhance Western security and promote democratic values. These discussions were eventually joined by France, the Low Countries, and Norway and in April 1949 resulted in the North Atlantic Treaty.
Organization
Spurred by the North Korean invasion of South Korea in June 1950 (see Korean War), the United States took steps to demonstrate that it would resist any Soviet military expansion or pressures in Europe. Gen. Dwight D. Eisenhower, the leader of the Allied forces in western Europe in World War II, was named Supreme Allied Commander Europe (SACEUR) by the North Atlantic Council (NATO’s governing body) in December 1950. He was followed as SACEUR by a succession of American generals.
The North Atlantic Council, which was established soon after the treaty came into effect, is composed of ministerial representatives of the member states, who meet at least twice a year. At other times the council, chaired by the NATO secretary-general, remains in permanent session at the ambassadorial level. Just as the position of SACEUR has always been held by an American, the secretary-generalship has always been held by a European.
NATO’s military organization encompasses a complete system of commands for possible wartime use. The Military Committee, consisting of representatives of the military chiefs of staff of the member states, subsumes two strategic commands: Allied Command Operations (ACO) and Allied Command Transformation (ACT). ACO is headed by the SACEUR and located at Supreme Headquarters Allied Powers Europe (SHAPE) in Casteau, Belgium. ACT is headquartered in Norfolk, Virginia, U.S. During the alliance’s first 20 years, more than $3 billion worth of “infrastructure” for NATO forces—bases, airfields, pipelines, communications networks, depots—was jointly planned, financed, and built, with about one-third of the funding from the United States. NATO funding generally is not used for the procurement of military equipment, which is provided by the member states—though the NATO Airborne Early Warning Force, a fleet of radar-bearing aircraft designed to protect against a surprise low-flying attack, was funded jointly.
Quick Facts
Date:
August 24, 1949 – present
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Membership
The table lists all 32 NATO members and the year they joined.