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Defense Intelligence Agency

Defense Intelligence Agency. Creation of a unified Department of Defense (DoD) in 1947–49 was not accompanied by the unification of defense intelligence activities. Each of the military services maintained its own intelligence organization; indeed, maintaining these distinct capabilities had been a major demand of the military during deliberations over the creation of the CIA. But there were also a number of intelligence requirements that were either interservice or departmentwide. Thus, additional intelligence organizations designed existed to meet these broader needs.

In 1961, Secretary of Defense Robert S. McNamara decided to rationalize much of the DoD's structure, and to improve resource management for broader defense intelligence efforts. The result was the Defense Intelligence Agency (DIA). Each service continued to argue, however, that it had unique intelligence needs that could not be met by a “joint” agency, and so the separate service units survived as well.

DIA is headed by a three‐star military officer, a position filled by rotation among the services. DIA has been through several major reorganizations in the past few years, although its major functions remain the same: the collection and analysis of intelligence specifically related to military requirements. Collection is carried out overtly by defense attachés and covertly by the relatively new Defense HUMINT (Human Intelligence) Service (DHS). The functions of attachés remain known to host governments; DHS collectors operate under cover. DIA produces independent analyses and contributes to communitywide intelligence estimates. It is one of three “all‐source” intelligence analysis centers (along with CIA and the State Department's Bureau of Intelligence and Research).

The DIA has sometimes found itself torn between its military customers (the Joint Chiefs of Staff and their organization) and civilian customers in the DoD. The Joint Chiefs may seek analysis to support specific or preferred positions; the civilians may prove skeptical of military‐produced analysis, which often tends toward more pessimistic assumptions about conflict and combat.

Competition with the military service intelligence units is less of a problem. But DIA has been among the intelligence agencies most severely hit by the end of the Cold War, which led to a 25 percent reduction in its personnel.
[See also Central Intelligence Agency; Intelligence, Military and Political.]


Mark M. Lowenthal , U.S. Intelligence: Evolution and Anatomy, 1984; 2nd ed. 1992.
Patrick Mescall , The Birth of the Defense Intelligence Agency, in Rhodri Jeffrey‐Jones and Andrew Lownie, eds., North American Spies: New Revisionist Essays, 1991.

Mark M. Lowenthal

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