The UN Security Council was formed immediately after WW2 and NATO was formed in 1949 with both organisations committed to providing post war collective security roles. NATO originally had 12 members and has grown since with Article 5 providing a security commitment of collective defence, originally against the threat of military action from the Soviet bloc and the Security Council was formed to provide collective global security which means that security is at the core of the role that both organisations provide. The organisations are similar in that they can and have taken significant military action. The Security Council has authorised the use of force in Korea in the 1950s and as a response to the Iraqi invasion of Kuwait, NATO has taken military action in the former Yugoslavia and elsewhere which means that both have a military role and significance in global politics. Equally both have had times when they could not agree on action such as the UN in Iraq and NATO in Ukraine. The organisations are similar in that they have focussed on tackling global issues of concern and significance, beyond conflict. There are numerous Security Council resolutions concerning issues such as the non-proliferation of nuclear weapons, use of children in armed conflict or support for criminal tribunals whilst NATO has been involved in issues such as anti-piracy or earthquake relief which illustrate a wide role and significance for both organisations. The organisations are similar in that they represent some of the most powerful and significant states in the world. The Security Council, permanent members, are 5 of the most powerful and significant states in the world judged both my economic and military power (US, Russia, UK, China and France), all are now nuclear powers and NATO is the most powerful and significant military regional collective of states with both nuclear powers and economically powerful member states including the US, UK, France, Canada etc. The organisations are similar in that they are exclusive and have a restricted membership. Membership of NATO may have increased to 30 (March 2023) over time but there are strict criteria for membership which include military forces being under firm civilian control, upholding of democracy etc and the UN Security Council permanent membership is restricted to just 5 states by Article 23 although ten further members are elected on rotation every two years.