How has NATO (North Atlantic Treaty Organisation) expanded over the years?
Enlargement of NATO is called the Article 10 process. ‘Any other European state’ may be invited, and requires approval of all current members.
At the end of the Cold War, NATO consisted of the United States, Canada, Portugal, Spain, France, the United Kingdom, Belgium, Luxembourg, Netherlands, Germany, Denmark, Norway, Italy, Greece and Turkey.
In securing Soviet agreement for a unified Germany’s membership, NATO promised that no foreign troops or nuclear weapons would be stationed in the former East Germany. Whether further eastward expansion of NATO was agreed, however, remains a point of controversy.
Poland, Hungary, and the Czech Republic joined in 1999. Membership was offered to Estonia, Latvia, Lithuania, Slovakia, Slovenia, Romania and Bulgaria in 2004, and Albania and Croatia in 2009.
More recent entrants to NATO include Montenegro in 2017 and North Macedonia in 2020.
As of today, three countries have applied: Finland, Sweden, and Ukraine: all after the Russian invasion of Ukraine in February (2022).
Ratification of the former two, (as at November 2022), remains at 28 out of 30 current members, with holdouts Hungary and Turkey.