in 1952 NATO in 1952 its membership has expanded periodically since NATO NATO’s expansion Member countries member countries established in 1949 Articles 5 and 6 NATO NATO in 1952 NATO NATO’s expansion established in 1949 Nato-Mitgliedsländer NATO its membership has expanded periodically since Member countries two purposes that are the basis for NATO unity NATO NATO’s expansion 28 members Member countries NATO’s expansion in 1952 28 members negotiations in 1999, 2004 and 2009 28 countries Nato-Mitgliedsländer 28 members http://www.nato.int/cps/en/natolive/topics_52044.htm NATO NATO Western countries NATO’s push into Eastern Europe incorporating 12 new members 12 countries Nato-Mitgliedsländer two purposes that are the basis for NATO unity Articles 5 and 6 founding members in 1952 http://www.nato.int/cps/en/natolive/topics_52044.htm