Article 5 of the North Atlantic Treaty forms the basis of NATO\u2019s collective defence system. It stipulates that an armed attack against one member of the Alliance is regarded as an attack against them all. However, this does not imply an automatic declaration of war or a uniform military response from every country: each ally determines for itself what action it deems necessary to assist the state under attack.<\/p>\n
The North Atlantic Treaty was signed in Washington on 4 April 1949. Its central feature was a system of collective defence.<\/p>\n
The bottom line. Article 5<\/a> It is simple: if one or more allies come under armed attack, the other NATO member states regard this as an attack on the entire Alliance. Following this, every country must come to the aid of the ally under attack. However, the text of the treaty contains a crucial provision: each state shall take such actions as she deems necessary<\/strong>, including \u2014 though not necessarily \u2014 the use of armed force. It is precisely this detail that is often overlooked in brief reports on NATO.<\/p>\n Article 5 does not mean that, following any incident, all 32 countries automatically declare war on the aggressor.<\/p>\n No. Each ally determines the form of assistance itself. This may include the deployment of armed forces, the strengthening of air defence, intelligence, naval or air operations, logistical support, cyber defence or other measures. In other words, there is a legal obligation to provide assistance, but the format of that assistance is not prescribed as being the same for everyone.<\/p>\n That is precisely why the phrase \u00abAn attack on one is an attack on all\u00bb<\/strong> accurately describes NATO\u2019s political principle, but does not imply the automatic triggering of a single, pre-determined military scenario.<\/p>\n There is no \u00abbutton\u00bb or automatic procedure in the North Atlantic Treaty that instantly \u2018triggers\u2019 Article 5.<\/p>\n If one of the NATO member states is subjected to an armed attack, the following measures will be taken North Atlantic Council<\/strong> \u2014 the Alliance\u2019s principal political body. The Allies assess the circumstances of the attack and decide whether a particular situation falls within the scope of the collective defence mechanism.<\/p>\n NATO\u2019s official clarification sets out two key conditions: an ally must be the victim of an armed attack, and the state under attack must request or agree to collective action under Article 5.<\/p>\n NATO decisions are taken by consensus \u2014 that is, not by a majority vote, but by agreement amongst the member states.<\/p>\n Article 4<\/strong> This relates to consultations. Any NATO country may ask its allies to convene if it considers that its territorial integrity, political independence or security is under threat.<\/p>\n There is no need to wait for an actual attack to happen.<\/p>\n Article 5<\/strong> \u2014 this is a collective defence mechanism following an armed attack.<\/p>\n In other words, to put it simply:<\/p>\n However, the application of Article 4 is not a prerequisite for Article 5.<\/p>\n Just once.<\/p>\n This happened following the terrorist attacks 11 September 2001 in the USA<\/strong>, when Al-Qaeda militants hijacked passenger aircraft and attacked World Trade Centre<\/a> and the Pentagon.<\/p>\n On 12 September, NATO declared for the first time in its history that an attack on the United States could be regarded as an attack on the entire Alliance. Once it had been established that the attack had been organised from abroad, the collective defence mechanism was invoked.<\/p>\n NATO subsequently carried out operations to patrol US airspace and conduct maritime surveillance in the Mediterranean Sea.<\/p>\nDoes Article 5 mean that all countries automatically enter the war?<\/h2>\n
How Article 5 is implemented<\/h2>\n
Article 4 and Article 5 of the NATO Treaty \u2014 what is the difference?<\/h2>\n
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How many times has NATO invoked Article 5?<\/h2>\n
Does Article 5 apply to Ukraine?<\/h2>\n