[1] The first artificial object to cross the Kármán line, the boundary between air and space, was MW 18014, an A-4 rocket launched by the German Heer on 20 June 1944 from the Peenemünde Army Research Center.
In both the United States and the Soviet Union, military space development began immediately after the Second World War concluded, with Wernher von Braun defecting to the Allies and both superpowers gathering V-2 rockets, research materials, and German scientists to jumpstart their own ballistic missile and space programs.
[2] In the United States, there was a fierce interservice rivalry between the U.S. Air Force and U.S. Army over which service would gain responsibility for the military space program, with the Air Force, which had started developing its space program while it was the Army Air Forces in 1945, seeing space operations as an extension of their strategic airpower mission, while the Army argued that ballistic missiles were an extension of artillery.
Ultimately, the Air Force's space rivals in the Army Ballistic Missile Agency, Naval Research Laboratory, and Advanced Research Projects Agency were absorbed by NASA when it was created in 1958, leaving it as the only major military space organization within the U.S. Department of Defense.
The first discussions of creating a military space service in the United States occurred in 1958, with the idea being floated by President Reagan as well in 1982.
Unlike in the United States, where the U.S. Air Force held preeminence in missile and space development, the Soviet Ground Forces, and specifically the Artillery of the Reserve of the Supreme High Command (RVGK), was responsible for missile and military space programs, with the RVGK responsible for the launch of Sputnik 1, the world's first artificial satellite on 4 October 1957.
[1] In 1998, the Chinese People's Liberation Army began creating its space forces under the General Armaments Department, before being reorganized and renamed as the People's Liberation Army Strategic Support Force Space Systems Department in 2015.