NATO
New membership in the alliance has been largely from Central and Eastern Europe, including former members of the Warsaw Pact. Accession to the alliance is governed with individual Membership Action Plans, and requires approval by each current member. NATO currently has two candidate countries that are in the process of joining the alliance: Bosnia and Herzegovina and the Republic of Macedonia.
In NATO official statements, the Republic of Macedonia is always referred to as the "former Yugoslav Republic of Macedonia", with a footnote stating that "Turkey recognizes the Republic of Macedonia under its constitutional name". Though Macedonia completed its requirements for membership at the same time as Croatia and Albania, who joined NATO in 2009, its accession was blocked by Greece pending a resolution of the Macedonia naming dispute. In order to support each other in the process, new and potential members in the region formed the Adriatic Charter in 2003. Georgia was also named as an aspiring member, and was promised "future membership" during the 2008 summit in Bucharest, though in 2014, US President Barack Obama said the country was not "currently on a path" to membership.
European integration
In fact, many EU member states are among the 28 NATO members. The Treaty of Brussels is considered the precursor to NATO. The North Atlantic Treaty was signed in Washington, D.C. in 1949. It included the five Treaty of Brussels states, as well as the United States, Canada, Portugal, Italy, Norway, Denmark and Iceland. Greece and Turkey joined the alliance in 1952, and West Germany did the same in 1955. Spain entered in 1982. In 1999, Hungary, the Czech Republic, and Poland became NATO members. Finally, Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovenia, and Slovakia joined in 2004. In 2009, Croatia and Albania joined. In 2008, Ukraine and Georgia were told that they will also eventually become members. The Republic of Macedonia's application process is finished, but it is blocked by Greece. Thus, 22 out of 28 NATO states are among the 28 EU members, another two are members of the EEA, and one more is an EU candidate and also a member of the European Union Customs Union.