US signals intelligence in the Cold War
The situation became a good deal more complex with the passage of the National Security Act of 1947, which created a separate Air Force and Central Intelligence Agency, as well as unifying the military services under a Secretary of Defense.
[7] While the US began to provide military supplies to the French, approximately at the time of the start of operations of the Armed Forces Security Agency in 1949, Indochina was a low COMINT priority.
During this period, several programs, potentially in violation of its foreign intelligence charter, the NSA (and its AFSA predecessor) monitored international telegram and selected voice communications of American citizens.
The related Project MINARET intercepted voice communications of persons of interest to US security organizations of the time, including Malcolm X, Jane Fonda, Joan Baez, and Martin Luther King.
COMINT, supported by information from other open and secret sources, showed a number of other military-related activities, such as VIP visits and communications changes, in the Soviet Far East and in the PRC, but none was suspicious in itself.
One colonel who participated in the GRI program was heard to remark that the information was so well appreciated by his soldiers that he had little trouble getting volunteers to go out at night and implant the equipment to make intercept possible, even though the sensors might need to be as close as 35 yards (32 m) to the enemy.
Since its mission was no longer exclusively identified with intelligence and security, ASA was withdrawn from G-2 control and resubordinated to the Army Chief of Staff as a field operating agency.
Again concealed by heavy redactions in the NSA history, it appeared that the French had intelligence of multiple Viet Minh units in the Dien Bien Phu area, but no good idea of their size.
Nevertheless, while some of the Joint Chiefs did recommend a US relief expedition, President Dwight Eisenhower, as well as Gen. Matthew Ridgway, having just come from the Korean command, rejected the idea of another land war in Asia.
While the IMINT organizations were most critical, an anecdote of the time, told by Juanita Moody, the lead SIGINT specialist for Cuba, that the newly appointed Director of NSA, LTG Gordon Blake, came by to see if he could help.
Two RB-47H aircraft of the 55th Reconnaissance Wing were modified during the Cuban Missile Crisis to work with Ryan Model 147 RPVs (Remotely Piloted Vehicle, terminology of that era for UAV)[9] launched from DC-130s.
The history mentions that his security organs were given a free hand by Ordnance Number 6 of January 1956, putting anyone deemed a threat to the defense of the state and public safety", at least in house arrest.
A special TDY [temporary duty] team was readied to fly to the ASA site at Clark Air Base to set up a second-echelon SIGINT reporting mission.
From the SIGINT standpoint, the Trail began at two major supply-heads, Vinh Linh and Đồng Hới, which were the intermediate headquarters running the infiltration-associated radio nets from 1959 until late 1963.
Essentially, the policy was that the South Vietnamese would be trained in basic direction finding using "known or derived" technical information, but, for security reasons, COMINT that involved more sophisticated analysis would not be shared.
It was also felt that for at least the near term, ARVN COMINT could not provide meaningful support, and the question was presented, to the State Department, if it was politically feasible to have US direction-finding teams operate inside South Vietnam.
[21] Although SIGINT personnel were present in 1960, Gilbert breaks the ASA involvement in Vietnam into four chronological phases,[18] which do not match the more recent NSA history by Hanyok, which is less focused on events with the US military.
"In the mad scramble for positioning that followed, the Viet Cong in the Nam Bo [Saigon] region directed subordinate elements to help soldiers, officers and others (politicians and security personnel) involved in the coup to escape.
The nature of BRAVO was not given, and the theater went back to ALPHA, apparently the lowest, by February 1961, when the intelligence community (IC) decided there was no chance the Soviets or PRC would join the fighting.
After deletions, the comment is made that the "more general traffic analysis situation was deemed barely sufficient to establish a "skeletal" technical continuity for radio station and network identification and provide data for a realistic estimate of the total communist communications problem.
[17] While the methods were not yet called MASINT, there was a Special Identification Techniques (SIT) facility at the ASA site at Clark AFB could use to do "radio fingerprinting" to recognize unique Morse code operator "fists".
Second, SIGINT detected the activation of specific weapons systems in the air defense network, such as SA-2 surface-to-air missiles (SAM), anti-aircraft artillery (AAA), and fighter interceptors.
[23] Under several code names, the last being UNITED EFFORT, the earlier combination of Okinawa-, and then Bien Hoa (Vietnam) based RB-47H ELINT aircraft and drones, originally planned for Cuba, was tried again in 1964, but without the blip-enhancing electronics that would make the North Vietnamese think it was a U-2.
Starting in 1965 and continuing until the end of the AGTR program in 1969, two "technical research" SIGINT ships, AGTR-1 Oxford and AGTR-2 Jamestown, sailed up and down the coast of Vietnam, acting as "firemen" to fill gaps in land-based coverage.
CEFIRM LEADER, first known as CRAZY DOG, was an attempt to build a system, called V-SCANARDF, the combined intercept, direction finding, and jamming for the 2-80 MHz frequency range.
The ACRP flights had been conducted by a detachment of Navy electronics squadron VQ-1, which relocated from Da Nang, South Vietnam, to Cubi Point Naval Air Station in the Philippines.
The Army would want to be able to recognize hostile artillery fire control radars, and also how to do tactical direction finding, traffic analysis, and field-level cryptanalysis against opposing ground forces.
The Army had both fixed and mobile intercept equipment appropriate for long-term listening to ground stations, while the Air Force and Navy could probe new foreign electronic systems as part of national-level intelligence goals.
During the Falklands War (Spanish: Guerra de las Malvinas/Guerra del Atlántico Sur) in 1982, Argentina used Boeing 707s, with visual reconnaissance capability only, to surveillance of the British Task Force.
"[35] Aside from public multinational activities such as the abortive 1983 Beirut barracks bombing, there were less obvious discussion and negotiation among nations seeking to deal with the immense cost of space-based SIGINT.
