Nato history: Highs and lows of defence pact agreed soon after Second World War THE North Atlantic Treaty Organisation (Nato) was first signed up to by Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom and the United States in April 1949 at a ceremony in Washington DC. On signing the treaty, countries commit themselves to participating in the political consultations and military activities of the organisation. They also sign up to collective self-defence. The 11 September attacks in the United States caused Nato to invoke Article 5 of its Charter for the first time in its history. That article says that an attack on any member shall be considered to be an attack on all. The invocation was confirmed on 4 October, 2001, when Nato, under secretary-general Lord (George) Robertson, determined that the terrorist attacks were eligible under the terms of the North Atlantic Treaty. The outbreak of the Korean War in June 1950 had been crucial for Nato, as it raised the apparent threat of all Communist countries working together. Though France showed solidarity with the rest of Nato during the Cuban Missile Crisis in 1962, its leader de Gaulle continued his pursuit of an independent defence by removing France's Atlantic and Channel fleets from Nato command. And in 1966, all French armed forces were removed from Nato command. Recent high-profile interventions by the alliance have included the overthrow of Muammar Gaddafi's regime in Libya and the war in Afghanistan. Nato led the bombing of Serbian capital Belgrade in 1999 during the conflict in the former Yugoslavia in response to ethic cleaning. There have also been recent Nato training missions in Iraq aimed at assisting the country's security forces. Nato forces are currently operating in Afghanistan, Kosovo, the Mediterranean, off the Horn of Africa and in Somalia.