Military power of NATO & Nordic Defence Cooperation

The North Atlantic Treaty Organization (North Atlantic Alliance) is an intergovernmental military alliance which was signed in Washington on 4 April 1949. NATO is a system of collective security: its independent member states agree to defend each other against attacks by others countries. NATO's main headquarters are located in Brussels. The following twelve states signed the treaty and became the founding members: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, Netherlands, Norway, Portugal, United Kingdom and United States. The following states joined the treaty after 1949: Greece, Germany, Turkey and Spain. Members who joined after the dissolution of the Soviet Union: Czech Republic, Hungary, Poland, Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, Slovenia, Albania, Croatia, Montenegro and North Macedonia.

Before and during the 2022 Russian invasion of Ukraine, several NATO countries sent army to reinforce the alliance's eastern flank. Alliance had deployed 40,000 troops along its 2,500 kilometres long Eastern flank to deter possible Russian aggression. On 5 July the North Atlantic Alliance members signed off on the accession protocols for Sweden and Finland and formally approved the decisions of the NATO summit.

Finland joined the alliance on 4 April 2023.

The Nordic Defence Cooperation (Nordefco) is a collaboration among the Nordic countries in the area of defense. Its five members are Denmark, Finland, Iceland, Norway, and Sweden. The organization was established on November 4, 2009 in Helsinki. The leadership of the organization is rotational.