As Russia began an attack on Ukraine this week, several nearby countries and members of the North Atlantic Treaty Organization turned to Western partners for support, citing the group's founding document as part of their response to the crisis.
Early Thursday, Estonia, Latvia, Lithuania and Poland — all four of which share borders with Russia and three with Belarus, where Russian troops have been stationed — were among those launching consultations under Article 4, according to a release from the Estonian government.
In NATO’s statement condemning the Russian attack on Ukraine, the organization mentioned that consultations of the North Atlantic Council were held under the provisions of Article 4 of the North Atlantic, or Washington, Treaty.
“We have decided, in line with our defensive planning to protect all Allies, to take additional steps to further strengthen deterrence and defence across the Alliance. Our measures and remain preventative, proportionate and non-escalatory,” the NAC said.
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The statement also mentioned Article 5 of the Washington Treaty.
“Our commitment to Article 5 of the Washington Treaty is iron-clad,” officials said. “We stand united to defend each other.”
Those two articles will likely be mentioned extensively in coming days after the Russian attack on Ukraine, but have significant differences. Here is a breakdown of what exactly those two articles entail.
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What Is the North Atlantic Treaty?
How NATO Countries Were Positioned at the Beginning of Russia's War in Ukraine
Source: North Atlantic Treaty Organization (NATO)
Credit: Andrew Williams/NBC
The North Atlantic Treaty, also known as the Washington Treaty, is the legal document that cemented the formation of NATO in 1949.
A total of 12 countries, including the United States, the United Kingdom, France and Italy, were among the founding members of the organization, a political and military alliance that was created in the context of providing a counterweight in Europe to the Soviet Union during the Cold War.
Over the years, 18 more members have joined the organization, including Turkey, Lithuania and Estonia, and most recently, North Macedonia in 2020. Ukraine is not a member of NATO, though it has signaled intentions that it wishes to join in the future.
Of the articles contained within the treaty, Articles 4 and 5 are those most commonly cited, including in the current conflict involving Russia and Ukraine.
What Is Article 4 of NATO?
Under Article 4 of the treaty, any member can call for a consultation of the North Atlantic Council when “the territorial integrity, political independence or security of any of the parties is threatened,” the article states. Calling upon Article 4 does not necessarily mean any action will be taken, but it intensifies communication among members.
On Thursday, NATO said that Bulgaria, the Czech Republic, Estonia, Latvia, Lithuania, Poland, Romania and Slovakia had all made requests for talks under Article 4.
In NATO’s statement around this most recent invocation of Article 4, it announced that they would proceed with “defensive planning” and other preparations in the event of further offensive military actions by Russia, but stopped short of announcing military intervention.
The article has now been invoked just seven times, according to NATO's website.
What Is Article 5 of NATO?
The most serious section of the treaty is Article 5, which is known as the “commitment clause.” Within this clause, every member of NATO agrees that it will consider an armed attack against any member state, whether in Europe or North America, as an attack against all 30 members of the organization.
Article 5 has only been invoked once in the history of NATO, when the United States called for joint action after the Sept. 11 attacks.
In their statement on the Russian attack on Ukraine, officials with the NAC said that their commitment to Article 5 was “iron-clad,” an important line in the sand considering the nations that Ukraine borders.
Ukraine, the second-largest by land in all of Europe, borders Poland, Slovakia, Hungary and Romania, all of whom are members of NATO. Belarus and Moldova, which border Ukraine to the north and south, respectively, are not NATO members.
As a result of the close geographic proximity to the conflict, NATO has indicated that Article 5 would be enacted if Russia were to launch any attacks against its member states, which would represent a dramatic escalation in the conflict.
Click here for complete coverage of the crisis in Ukraine.