The North Atlantic Treaty Organisation (NATO) is the world's most powerful regional defence alliance. NATO is an intergovernmental military alliance based on the North Atlantic Treaty that was signed on the 4th of April, 1949. The founding members of the Alliance are Belgium , Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands , Norway, Portugal, the United Kingdom and the United States . NATO has grown in numbers on seven occasions since its creation. From 1952 to 2009 sixteen new members have joined. These members, in order of year added, are Greece, Turkey, Germany, Spain, the Czech Republic, Hungary, Poland, Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, Slovenia, Albania and Croatia. All NATO decisions are the collective will of all these 28 member counties.
NATO cooperated with partner countries belonging to various international structures. It works with the Partnership for Peace program that was established in 1994. Members of the Partnership for Peace (PfP) include the Commonwealth Independent States which are Armenia, Azerbaijan, Belarus, Kazakhstan, Kyrgyzstan, Moldova, Russia, Tajikistan and Uzbekistan. These countries are all members of the Euro-Atlantic Partnership Council (EAPC). Other partner countries of NATO that are part of PfP and EAPC are Austria, Bosnia and Herzegovina, Finland, Macedonia (formerly Yugoslav), Georgia, Ireland, Malta, Montenegro, Serbia, Sweden, Switzerland, Turkmenistan and Ukraine. NATO's Mediterranean Dialogue involves Algeria, Egypt, Israel, Jordan, Mauritania, Morocco and Tunisia. NATO's Istanbul Cooperative Initiative (ICI) includes Bahrain, Qatar, Kuwait and the United Arab Emirates. NATO also has 4 contact countries that are not part of the related structures. These countries are Australia, Japan, New Zealand and South Korea. These countries share similar strategic concerns and key Alliance values.
NATO's main aim when it was created was to "safeguard the freedom, common heritage and civilisation" of its members by promoting "stability and well-being in the North Atlantic area". NATO has a collective defence policy. This policy means that an attack against one or several members of NATO is considered an attack against all. The first time that this policy came into action was when the 2001 large-scale terrorist attacks hit New York and Washington D.C.
"The basic premise of NATO was that Europe’s security was the United States security and vice versa."- Barack Obama, US President