NATO's northern command and reinforcement problem

Norway's entry into NATO in 1949 created the alliance's only direct northern European border with the Soviet Union during the Cold War. Allied Forces Northern Europe and SACLANT connected territorial defence with the movement of American forces across the Atlantic. Early Cold War planning also treated Norway as a forward base for strategic bombers, while Arctic routes for bombers and intercontinental ballistic missiles drove early-warning installations in Greenland, Canada, and Alaska. NATO exercised reinforcement operations involving up to 100,000 American and other Allied personnel because Soviet submarines and surface forces could threaten the supply routes on which Europe's defence depended. Forward maritime strategy sought to contest the Norwegian Sea. Attack submarines and carrier groups would put pressure on Soviet northern forces so that Moscow had to divert ships, aircraft, and submarines to protect its ballistic-missile submarines.