FAS

Managing the Department of Defense: An Overview

11.18.19 | 1 min read | Text by Steven Aftergood

More than 2.8 million U.S. military and civilian defense personnel were deployed in more than 150 countries around the world last year.

No one person can fully comprehend the workings of the Department of Defense. It is a massively complicated bureaucratic construct composed not only of the military services (Air Force, Army, Navy, Marine Corps), but also of numerous defense agencies, “DoD field activities,” and unified combatant commands, among other components.

An internal Pentagon publication entitled “Organization and Management of the Department of Defense,” presented an overview of this mammoth enterprise as of March 2019.

The 168 page document provides detailed information on the Department’s structure and governance, along with various other significant data that can be hard to locate.

So one finds, for example, that there were a total of 1,310,731 active U.S. military personnel at the end of 2018, including no fewer than 229,611 officers.

There were 2,882,061 U.S. military and civilian defense personnel deployed in 158 countries, which are broken down in the document by the number of personnel and their location abroad — except for Iraq, Syria and Afghanistan, where deployment figures are currently restricted.

The Pentagon document has already been overtaken by events in some respects. Instead of the 19 defense agencies it lists, there are now 20 — including the new Space Development Agency. And instead of 10 unified combatant commands, there are now 11 — including the new U.S. Space Command.

Additional material about DoD organization and management can be found in the new DoD financial audit for FY 2019, published last week.

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