TACAMO is a United States military system of survivable communications links designed to be used in nuclear warfare to maintain communications between the decision-makers and the triad of strategic nuclear weapon delivery systems. Its primary mission is serving as a signals relay, where it receives orders from a command plane such as Operation Looking Glass, and verifies and retransmits their Emergency Action Messages (EAMs) to US strategic forces. As it is a dedicated communications post, it features the ability to communicate on virtually every radio frequency band from very low frequency (VLF) up through super high frequency (SHF) using a variety of modulations, encryptions and networks, minimizing the likelihood an emergency message will be jammed by an enemy. This airborne communications capability largely replaced the land-based extremely low frequency (ELF) broadcast sites which became vulnerable to nuclear strike.

Looking Glass is the historic code name for an airborne command and control center operated by the United States. In more recent years it has been more officially referred to as the ABNCP. It provides command and control of U.S. nuclear forces in the event that ground-based command centers have been destroyed or otherwise rendered inoperable. In such an event, the general officer aboard the Looking Glass serves as the Airborne Emergency Action Officer (AEAO) and by law assumes the authority of the National Command Authority and could command execution of nuclear attacks. The AEAO is supported by a battle staff of approximately 20 people, with another dozen responsible for the operation of the aircraft systems. The name Looking Glass, which is another name for a mirror, was chosen for the Airborne Command Post because the mission operates in parallel with the underground command post at Offutt Air Force Base.