It is possible to consider the rise of intelligence satellites as the starting point of the use of space for military purposes. The priority in such projects was to develop platforms to gather strategic intelligence pertaining to the production, storage and deployment of nuclear weapons.

Although the Soviet Sputnik 1 was the first satellite to be placed into orbit in 1957, both superpowers had already been engaged in development of satellites as of mid-1950s for reconnaissance and intelligence purposes. There are some operational benefits in the use of satellites for reconnaissance, surveillance and intelligence missions. These can be summarised as follows:  

Immunity from obstacles like airspace and air threats: There is not a binding international norm, system or practice to control or prevent the course of a platform moving in space, which lies beyond the borders of national airspace. Accordingly, it is possible to gather intelligence from an enemy state via satellite also during peacetime.