World War II: Home Front
 

The home front served as headquarters, training site, and mobilization base of military intelligence during World War II. To meet the increased counterintelligence demands, the Army replaced the Corps of Intelligence Police (CIP) at the beginning of 1942 with a new organization, the Counter Intelligence Corps. For the first time, officers were assigned to this elite organization, and soldiers obtaining the rank of sergeant were given the title of “Special Agent.” Whether conducting background checks on individuals holding sensitive positions with the War Department or checking out an act of espionage or sabotage, the CID’s authority and arrest powers were represented by the badges and credentials carried by the officers and agents.

In June 1942, the army acquired Arlington Hall Junior College to house the rapidly expanding Signal Intelligence Service (SIS). The former elite girl’s school became the permanent headquarters for the Army cryptologic organization and the scene of one of the great triumphs of Army intelligence. The analysts of the Signal Security Agency (SSA) (formerly the SIS) succeeded in breaking into and exploiting the encryption systems used by the Imperial Japanese Army. The intelligence thus produced greatly shortened the course of the war and saved countless lives. Access to Arlington Hall was restricted to personnel on official business, and a great effort was undertaken to indoctrinate all personnel in the necessity of maintaining security. Identification badges had to be worn at all times.