As an historic aside.... Those familiar with the history of US nuclear intelligence operations 1946- 1950 (esp Douglas Mackiernan- CIA- Xinjiang) know about early programs regarding "long range detection of nuclear explosions". In the pre-satellite era. As part of a multi front, global effort, The US fielded detection devices, of different types (sound) at US Embassies in Russia-facing-third countries, like China, Germany etc. as well as radioactive particle filters aboard a fleet of planes flying near the borders. That's the 'long range' history behind what you read here--circa 1980's. Since US technical means 1949 provided first detection of Russia's first nuke test, technicians would have at least aspired, in the 1980's, to go one better and detect the material it self before explosion. Thats what I read in the mention of NPB in this declassified document. See "Spying without Spies" regarding birth of such national technical means. ... and "Into Tibet" about Mackiernan's operation.
Assistant Professor of History and International Affairs | Space Policy Institute
This 1983 declassified memo discusses “Porcupine” which was a concept for space-based pods containing hit-to-kill interceptors to protect space-based components of the Strategic Defense Initiative.
