North Atlantic Treaty

Agreement signed on 4 April 1949 by Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the UK, and the USA, in response to the Soviet blockade of Berlin June 1948–May 1949. They agreed that ‘an armed attack against one or more of them in Europe or North America shall be considered an attack against them all’. The North Atlantic Treaty Organization (NATO), which other countries have joined since, is based on this agreement.

Signed at Washington, DC, the agreement indicated that the USA associated itself with the Western European countries in security arrangements for their common or mutual defence against possible aggression. The pact had its origins in the history of the two years 1947–48, during which failure to come to terms with the Soviet Union and its satellites forced the Western countries to seek economic and security arrangements among themselves. The immediate stimulus was the signing of the Treaty of Brussels in 1948 which brought Britain, France, Belgium, the Netherlands, and Luxembourg together in a pact for mutual defence and social and economic cooperation.