A political military alliance, it was the result of Cold War tensions between the United States and Western Europe on one side and the Soviet Union on the other. The continued stationing of large amounts Soviet forces in Eastern Europe made a common defense organization necessary.
The NATO alliance has sought to standardize on a variety of military equipment. Ships, aircraft and armored vehicles are often purchased by multiple NATO member countries. Rifle magazine designs are standardized for interoperability purposes, so that a British SA-80 rifle will take magazines from an Norwegian Heckler and Koch 416.