United States Army Security Agency ] The United States Army Security Agency ( ASA ) was the United States Army ' s signal intelligence branch . The Latin motto of the Army Security Agency was " Semper Vigilis " ( Vigilant Always ) , which echoes Thomas Jefferson ' s declaration that " The price of freedom is eternal vigilance . " The Agency existed between 1945 and 1976 and was the successor to Army signal intelligence operations dating back to World War I . ASA was under the [ operational ] command of the Director of the National Security Agency ( DIRNSA ) , located at Fort Meade , Maryland ; but had its own tactical commander at Headquarters , ASA , Arlington Hall Station , VA . Besides intelligence gathering , it had responsibility for the security of Army communications and for electronic countermeasures operations . In 1977 , the ASA was merged with the US Army ' s Military Intelligence component to create the United States Army Intelligence and Security Command ( INSCOM ) . History . Composed of soldiers trained in military intelligence , the ASA was tasked with monitoring and interpreting military communications of the Soviet Union , the People ’ s Republic of China , and their allies and client states around the world . The ASA was directly subordinate to the National Security Agency and all major field stations had NSA technical representatives present . All gathered information had time - sensitive value depending on its importance and classification . Information was passed through intelligence channels within hours of intercept for the lowest - priority items , but in as little as 10 minutes for the most highly critical information . ASA personnel were stationed at locations around the globe , wherever the United States had a military presence – publicly acknowledged or otherwise ( Peshawar , Pakistan ) . In some cases such as Eritrea , it was the primary military presence . The 13th USASA Field Station , outside of Harrogate , England in what is now North Yorkshire was and is a primary listening post . It was subsequently turned over to the British and became an RAF station . It is called RAF Menwith Hill , and was the site of peace protests . Vietnam War . Although not officially serving under the ASA name , covertly designated as Radio Research , ASA personnel of the [ 3rd Radio Researchd Unit were among the earliest U . S . military advisors in Vietnam ; 3rd RRU later grew to become the 509th Radio Research [ Group ] . The first battlefield fatality of the Vietnam War was Specialist 4 James T . Davis ( from Livingston , Tennessee ) who was killed on 22 December 1961 , on a road near the old French Garrison of Cau Xang . He had been assigned to the 3rd Radio Research Unit at Tan Son Nhut Air Base near Saigon , along with 92 other members of his unit . Davis Station [ at Tan Son Nhut ] was named after him . President Lyndon Johnson later termed Davis " the first American to fall in the defense of our freedom in Vietnam " . Most ASA personnel processed in country through Davis Station ; others attached to larger command structures prior to transport to Vietnam processed in with those units . For example , the 601st Radio Research Unit , attached to the 198th Light Infantry Brigade , processed in with that brigade . ASA personnel were attached to Army infantry and armored cavalry units throughout the Vietnam War . Some select teams were also attached to MACV / SOG and Special Forces units . Some teams were independent of other army units , such as the 313th Radio Research Brigade at Nha Trang . Many ASA personnel remained in Vietnam after the 1973 pullout of US Army combat forces and remained present until the Fall of Saigon in April 1975 . Personnel . ASA military occupational specialties ( MOSs ) included voice intercept operators , who are usually linguists with MOS 98G ( plus a four character suffix ( pLnn ) to indicate proficiency level and language code ) , morse code intercept operators ( " Ditty Boppers " or sometimes " Hogs " for their 05H designation ) , non - morse ( teletype and voice ) intercept operators ( 05K ) , communications security / signal security specialists ( 05G ) whose monitoring of military communications often led to soldiers being punished ) , direction - finding equipment operators ( " Duffys " for their 05D designation ) , computer system operators ( 74E ) who operated equipment at the NSA headquarters and out in the field , Crypto - Clerks ( 72B ) , Cryptanalysis / Cryptanalytic Technician ( crippies ) , ( 98B ) , communications traffic analysts ( 98C ) , voice intercept operators ( Monterey - Marys ) ( 98G ) non - communications intercept / analysts ( 98J – RADAR and telemetry ) electronic cryptographic maintenance technicians ( 32F - G , and 33S ) , and Specialized Teletypewriter Equipment Repairman ( 31J B3 ) . Electronic Maintenance MOS ' included 33B intercept equipment repairman , 33C Intercept Receiver Repairman , 33D Intercept Record System Repairmen , 33F Digital Demultiplex Intercept Systems Repairman , 34F Digital Systems Terminal Equipment Repairman and 33G Electronics Countermeasures System Repairmen and a 44 man Special Operations Detachment or field teams to conduct clandestine combat operations , among others . ASA had its own separate training facilities , communication centers and chain of command . In 1976 , all 33 MOS designations were consolidated into one field , 33S Electronic Repairman . The designation became Electronic Warfare Intercept Systems Repairman . Other specialists intercepted and analyzed radar transmissions . Others intercepted communications and data transmissions from missiles and satellites . These occupations , which required a top secret clearance with Special Intelligence / crypto special clearances , were essential to U . S . Cold War efforts . ASA units usually operated in four groups using revolving shifts to provide coverage twenty - four hours a day , seven days a week . ASA troops were not allowed to discuss their operations with outsiders – in fact , they could not talk among themselves about their duties unless they were in a secure location . Even today , decades after they served , some of the missions still cannot be discussed . ASA personnel processing out of sensitive operations were debriefed and signed a document specifying a forty - year elapsed time before they could discuss what they had done or observed . Owing to the sensitivity of the information with which they worked , ASA personnel were subject to travel restrictions during and sometimes after their time in service . The activities of the U . S . Army Security Agency have only recently been partially declassified . This turn of events has been accompanied by the appearance of a small number of ASA memoirs and novels ( see the list below ) . Human resources ( 1945 – 1965 ) . The ASA , during the majority of the years of its existence , from 1945 to 1978 , was largely a “ Cold War ” operation . ASA enlisted troops were usually recruited from the top range of scores in aptitude tests given during initial induction . The Army itself exhibited little concern for the ASA until 1965 , as it was a " Joint venture " essentially under the control of a civilian organization . However , there was a general concern in the Department of the Army that enlisted technicians of all kinds should be given recognition and adequate pay in order to retain them . Accordingly , in 1954 , Army Regulation 615 – 15 created the grades of Specialist s Four , Five , Six , and Seven , ( SP4 , SP5 , SP6 , SP7 ) corresponding to Corporal ( E4 ) , Sergeant ( E5 ) , Staff Sergeant ( E6 ) , and Sergeant First Class ( E7 ) , in order to get around the general Table of Organization and Equipment restrictions on the total number of individuals ( normally regular NCOs ) , who could be placed in these grades . Promotion in the specialist grades was fairly rapid with specialists with two years of military experience reaching E5 and E6 in another two years . Due to the long training requirements , and initial four - year enlistment was normal . However despite sometimes intensive efforts to retain personnel , reenlistment rates were very low . In 1958 , DA Reg 344 – 303 also created Specialist Grades Specialist Eight and Nine . There were never more than a handful of Specialist 7 ’ s in the ASA and no individual in the ASA was ever promoted to the grades of Specialist 8 or 9 before these top grades were eliminated in 1965 . . Promotion to warrant officer after E7 was the normal military progression in ASA units . The officers within the ASA were generally commissioned into the Signal Corps branch since there was no separate branch for ASA . Effective in 1967 , the Military Intelligence ( MI ) branch stood up and officers were commissioned into MI . In today ’ s Army , modern technology has largely replaced the specific tasks performed by most ASA troops . The current Army MOS Military Intelligence 35 series involving SIGINT , requires the same high security clearance levels as the old ASA standards . However , the modern Soldier in the MOS 35 series actually perform the full range of now computer - driven SIGINT functions that the average ASA trooper never came close to performing . The educational level of an ASA linguist in the late 1950s is typified in a memoir by a graduate of ALS class R - 12 - 80 , the school ’ s 80th 12 - month class in Russian . He had an M . A . in one of the humanities , and had been working on a PhD . In addition , ASA specialists and linguists were recruited from high - scoring inductees . Specialist in different MOS were trained at Arlington Hall Station , Fort Devens Massachusetts and sometimes at Signal Corps facilities while those selected to be linguists were given 9 to 12 month language courses which were usually taught by native born instructors at DLI at the Presidio of Monterey , CA and in Washington DC . Native born speakers in Spanish , German and others were also recruited , as well as personnel whose previous assignments and experience had gained them proficiency in a language . From 1965 to 1973 , Major General Charles Denholm , supervised the integration of the ASA with the rest of Army Military Intelligence and the organization underwent a dramatic change , including a vast increase in size and scope and a completely changed relationship with the NSA during the final period of its existence . By this point in time it was not , of course , the traditional " ASA " .