The acronym SOCOM is usually a reference to the United States Special Operations Command headquartered at MacDill Air Force Base, Florida. USSOCOM is one of the nine Unified Combatant Commands which exercise operational control U.S. combat forces. Four of the commands are geographically concentrated in their missions (five if you count the small geographic area of responsibility left to United States Joint Forces Command in the wake of its transformation from United States Atlantic Command). The others are "functionally" concentrated for lack of a better term. Of these non-geographic commands, USSOCOM is a bit of an oddity. This is primarily due to its independent purchasing authority. Under U.S. law, it falls to the four services to "organize, train, and equip" forces for war. When it comes time to actually conduct military operations, the Joint community runs the operations through the Unified Combatant Commands. Thus the services usually buy stuff and the Unified Combatant Commands carry out operations with the stuff and people provided by the services. However, since USSOCOM controls forces with such different equipment requirements, it has the authority to purchase stuff. It's an odd beast created out of the 1986 Goldwater-Nichols Department of Defense Reorganization Act. To some, it's a fifth service running around with scant oversight and little integration with the rest of DoD. To others, it's an example of what "jointness" can achieve in terms of increased operational capabilities.
More, I'm sure, than you care to know.
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