Spy ship

[2] Starting in 1933 as a station ship she was assigned to monitor internal Japanese Fleet frequencies and direction finder azimuths.

Gold Star and ground stations provided significant intelligence before the Japanese attack on Pearl Harbor on 7 December 1941.

[3] Spy ships in the modern sense of being specially built and entirely dedicated to intelligence tasks came into being during the early Cold War, and they are in use by all major powers.

Their uses, in addition to listening in on communications and spy on enemy fleet movements, were to monitor nuclear tests and missile launches (especially of potential ICBMs).

[citation needed] As it is located much closer to the surveilled area than a fixed installation (given a close by shoreline), the monitoring is usually much more efficient and in some respects better than even that of spy satellites.

After the Cuban Missile Crisis, the Joint Chiefs of Staff authorized a counter AGI program for United States destroyers to come alongside the AGIs to push against them, foul their screws with steel nets, and focus high power electromagnetic transmitters to burn out the amplifying circuitry of their electronic sensors.

[10] In 1972, as the U.S. and U.K. partners started operating radar station Cobra Mist, it garnered attention from many Soviet spy trawlers.