US Army Military Intelligence History: A Sourcebook - Fort Huachuca ...

World War I Era5-Artillery Target Development, 6-Radio Intelligence and Carrier Pigeons, and 7-Dissemination and G2Journal.G2B (Secret Service): 1-Counterespionage Policy and Investigation of Atrocities, 2-Dissemination ofInformation from Secret Sources and Control of Intelligence Contingency Funds, and 3-Index of Suspects,Control of the Civil Population and Counterespionage Operations.G2C (Topography)G2D (Censorship) 1-Press Relations and Press Censorship, 2-Censorship Regulations and Postal andTelegraphic Censorship, and 3-Photograph and Movie Censorship and Visitors.G2E (Intelligence Corps)Nolan had far-reaching plans for his intelligence network, extending it beyond the collection of battlefieldintelligence. He wanted his G-2 to reach beyond the front in France and Belgium and collectstrategic intelligence from theaters in Italy and Macedonia, places where the AEF might be expected tofight later in the war. For this purpose he formed a G-2 Secret Service unit which also had a counterespionagestaff with stations in neutral countries.In the AEF, intelligence was now recognized as a critical element of war-fighting. Up and down thecommand structure could be found G-2s. Starting at the infantry battalion, an intelligence staff officercould call upon a reconnaissance platoon of 15 scouts, 11 observers, and 2 snipers, a total of 28. Theregimental intelligence officer had eight observers. Each division had a G-2 who also was assigned mento act as observers. At the Corps level, the G-2 could rely upon observation posts, balloons, aerosquadrons with both visual and photographic recon, and flash or sound-ranging teams which targetedenemy artillery. These tools gave him the ability to look five miles beyond the enemy’s front-line positions.In addition to those assets at corps, the field army headquarters had a radio intelligence sectionworking on decoding and translating enemy messages. Intercept was done by a Signal Corps radiosection at GHQ in Chaumont, using a combination of direction-finding equipment, listening posts, andinduction coils placed near enemy ground lines. Communications security was undertaken by the SignalCorps.A Radio Intelligence Subsection (RIS) was created under the American Expeditionary Force G-2 earlyin 1917, long before the first American fighting forces would arrive. Cooperating with their French andBritish allies counterparts, they prepared for the coming joint operations.When the American First Army arrived in France, a three-man RIS was formed on 12 June 1918 with“Code” and “Goniometric” (Direction Finding) sections. Commanded by First Lieutenant Charles H.Matz, it was enlarged to three officers and eight men by the armistice. The First Army RIS was responsiblefor analyzing and translating communications intercepted by the Signal Corps radio intelligence operators,and locating enemy radio stations based on bearings plotted by Signal Corps “gonio” operators.These Signal Corps radio intelligence personnel had arrived in France in December 1917 and had undergonetraining enabling them to intercept messages at the rate of 25 words per minute and to translate 15words per minute from the German. All of their intercept, direction-finding, or wire-tap stations were tiedinto the division RIS.The goniometric teams used the portable SCR-83 radio receiving sets with six-foot-square antennas.Two stations could triangulate signals transmitted by enemy radios and pinpoint their locations. Byanalyzing traffic and combining that information with direction-finding, they could determine the depth ofthe enemy echelons and compile a daily order of battle.One indication of the value of this kind of information occurred at the battle of Saint Mihiel in September1918 when American commanders, believing the Germans to have withdrawn from the salient, consideredsending up the infantry without artillery support. Goniometric stations warned that all the enemyradio stations were still operating in their former positions, a solid indicator the enemy was still there.General John Pershing decided to attack only after a four-hour artillery preparation, thus saving the livesof considerable infantrymen. In that same battle, SIGINT alerted the Americans to a German counterattack,giving the strength and exact time three hours before it was launched.83