Spain joined the Alliance on 30 May 1982, despite strong public opposition. The end of the Franco dictatorship in 1975, the military coup of 1981 and the rise of the Socialist Party (PSOE), the main opposition party, initially opposed to NATO membership, created a difficult social and political context, both nationally and internationally. At the NATO Summit in Prague on 21-22 November 2002, Member States agreed to make changes to ensure that the Alliance remains a central mechanism to meet the security needs of its members. These included expanding the organization to new members, improving relations with NATO partner countries and expanding the Alliance. Since its inception in 1949, NATO has welcomed eight new members for a total of 30 members. Twelve countries participated in the creation of NATO: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom and the United States. In 1952, Greece and Turkey became members of the Alliance, followed by West Germany (1955) and Spain (1982). In 1990, with the reunification of Germany, NATO became the former GDR country. Between 1994 and 1997, wider forums for regional cooperation were established between NATO and its neighbours, including the Partnership for Peace, the Mediterranean Dialogue Initiative and the Euro-Atlantic Partnership Council. In 1997, three former Warsaw Pact countries, Hungary, the Czech Republic and Poland, were invited to join NATO.
Following this fourth enlargement in 1999, the Group of Baltic States was established in May 2000 in Vilnius and seven Eastern European countries to cooperate and continue NATO membership. Seven of these countries joined the fifth enlargement in 2004. Albania and Croatia joined the sixth enlargement in 2009, Montenegro in 2017 and Northern Macedonia in 2020. The NATO Parliamentary Assembly (NATO PA) is a body that sets global strategic objectives for NATO, which meets at two meetings a year. NATO-AP interacts directly with the parliamentary structures of national governments of member states that appoint permanent members or ambassadors to NATO. The NATO Parliamentary Assembly is made up of members of the North Atlantic Alliance and 13 associate members. However, it is officially a different structure from NATO and aims to discuss together MEMBERS of NATO countries to discuss security policy in the NATO Council. Each member appoints an ambassador to NATO. They place officials in NATO committees and send officials to discuss NATO affairs. The President, the Prime Minister, the Minister of Foreign Affairs or the head of the Ministry of Defence could be one of those representatives. When Iceland signed the treaty in 1949, it had no armed forces - and it still does not. There are no legal barriers to their education, but Iceland has chosen not to have one.
However, Iceland has a coastguard, national police, air defence system and volunteer expedition force. Since 1951, Iceland has also enjoyed a long-standing bilateral defence agreement with the United States. In 2006, U.S. forces were withdrawn, but the defense agreement remains valid. Since 2008, air policing has been regularly provided by NATO allies. The seven countries had participated in POPs before joining NATO.