DCA assumed responsibility for the Minimum Essential Emergency Communications Network (MEECN), a subsystem of WWMCCS, in December 1971. The MEECN was developed to assure the timely receipt of emergency action messages by worldwide U.S. nuclear forces under nuclear attack by the Soviet Union. DCA served as the MEECN system engineer and provided the broad engineering necessary to ensure a more survivable future network with compatible, interoperable, and secure subsystems. The MEECN was a dedicated overlay on day-to-day communications systems. It involved the use of command, control, and communications relay aircraft, missiles with ultra-high-frequency broadcast systems, specialized satellites, and ground radio broadcast systems. It was a special-purpose, dedicated, hardened, high-confidence emergency system for passing emergency action messages. The MEECN continues to provide secure, high-fidelity, jam-resistant, and survivable communications links between the national command authorities and the strategic nuclear forces.
A DoD directive issued in the early 1970s appointed DCA as the system architect for all defense satellite communications. A major new DCA headquarters staff directorate, the Military Satellite Communications (MILSATCOM) System Office was created to discharge the new role. As the system architect, DCA coordinated all defense satellite communications planning and programs to avoid duplication and ensure communications interoperability among the diverse systems serving the complete spectrum of defense needs. The first comprehensive MILSATCOM architecture was published in 1976. In February 1976, Phase II of DSCS III program was initiated by DCA, when it awarded a contract to the General Electric Company to produce two demonstration flight satellites to demonstrate that viability of the DSCS III program.