*** The USA Military's Force Structure: A Primer

from the Congressional Budget Office

For the first time in nearly two decades, the Department of Defense (DoD) has experienced sustained budget cuts in recent years: Annual appropriations (excluding additional appropriations for ongoing military operations) for 2013 through 2016 averaged about 5 percent less, in nominal terms, than the funding in 2012.

The possible need to accommodate constraints on DoD's budget in the future - because of caps on discretionary spending through 2021 enacted in the Budget Control Act of 2011, as amended - raises the question of how best to prioritize the various tasks that the department performs and how best to assess any proposed changes to the force. At the same time, the enormous size and complexity of DoD, the many specialized organizations it includes, the wide array of weapon systems and platforms it operates, and the complexity of its budget documents make the task of understanding how the department operates - and how its budget could be changed - daunting to many observers.

To increase policymakers' understanding of the choices that the nation faces when considering DoD's budget, the Congressional Budget Office has prepared this primer on the structure of the armed forces. There are many different ways to approach DoD's budget; for the purposes of this analysis, CBO treats DoD as an organization that produces, sustains, and supports combat units. The number and type of combat units, as well as the personnel and equipment they contain, are referred to as the force structure. To produce this primer, CBO developed an analytic model of the military's force structure in which DoD's costs are viewed as inputs necessary to operate and sustain the force. The advantage of that treatment is that it provides a clear view of the trade-offs that would be involved if policymakers wanted to reduce DoD's budget through cuts in the force structure - each element of the force structure has a cost associated with it, the costs of different elements can be compared, and it is possible to say how much of the force structure would have to be cut to generate a given amount of savings.