The term 'PART OF NATO' can be broken down into four crossword solutions: ATLANTIC (8 letters), TREATY (6 letters), ATL (3 letters), and ORG (3 letters). The North ATLANTIC TREATY Organization, commonly known as NATO, is an intergovernmental military alliance between 30 North American and European countries. The ATLANTIC TREATY, signed in 1949, established the organization and its purpose of collective defense. The acronym 'ATL' stands for ATLANTIC, while 'ORG' stands for organization. Together, these four solutions form the term 'PART OF NATO'.