The Russian intervention in Crimea in 2014 lead to strong condemnation by NATO nations , and Poland invoked Article 4 meetings . At the subsequent 2014 Wales summit , the leaders of NATO 's member states formally committed for the first time spend the equivalent of at least 2 % of their gross domestic products on defence by 2024 , which had previously been only an informal guideline . In 2015 , five of its 28 members met that goal . At the beginning of 2018 , eight of the 29 members either were meeting the target or were close to it ; six others had laid out plans to reach the target by 2024 as promised ; and Norway and Denmark had unveiled plans to substantially boost defense spending ( including Norway 's planned purchase 52 new F-35 fighter jets
2014 Wales summit
2014 Wales summit
History of NATO