
Congress has authorized some $738 Billion in defense spending for the current year and wrangling is already underway for FY21 (and, indeed, FY22, FY23, and FY24). The Navy wants a bigger share of the pie, citing the National Security Strategy. The Army wants a bigger share of the pie, citing the disproportionate share of the load it’s been bearing in ongoing operations. The Marine Corps claims to be by far the most frugal. And that’s to say nothing of the Air Force and the new Space Force.
But AEI’s Mackenzie Eaglen points to a major problem: everyone is using different numbers to represent what they’re currently getting. And none of them are wrong.
Here’s an example. A common but flawed assumption persists that the total budget for the Department of Defense is divided roughly equally between the Army, Air Force, and Navy.

In the fiscal 2020 defense budget request, based on the pool of money allocated to the base budgets of the services alone, 35.6 percent goes to the Air Force, 27.9 percent goes to the Army, and 36.4 percent goes to the Navy (including the Marine Corps).
But those numbers are malleable. Whether a service chief uses only base budget numbers in making his case matters. Same with a service secretary including Overseas Contingency Operations (OCO) dollars in his or her arguments—especially now that a significant chunk of “emergency” funds are for entirely knowable and predictable base budget activities.

Therefore when you include OCO spending, 34.6 percent goes to the Air Force, 30.7 percent goes to the Army, and 34.7 percent goes to the Navy. Still, some of the services say this is an unfair analysis depending on their portion of global combatant commander requirements compared to their budget.
Whether overseas contingencies should be included in the base budget or remain a separate category is a topic that can be argued either way. Ditto whether it’s reasonable to include OCO in talking about how much a particular service is getting.
The Army, not unreasonably, says that it’s not. Its share of the budget goes up considerably when including OCO. And, yes, it’s spending that money. But, as the name implies, it’s spending it on operations, not investing in future capability. If the debate is about preparing for a future war with China and/or Russia—which the National Security Strategy is predicated on—then we shouldn’t count OCO.
The Navy, not unreasonably, says that we have to include OCO because, well, we’re spending money on overseas contingencies rather than investing in future capabilities. And the Navy needs to do the latter if it’s going to fulfill its mission. Oh, and for these purposes, the Navy includes the Marine Corps.
The two charts presented thus far obscure the overall debate, though, because the three departments (Army, Navy, and Air Force) and four/five services (the Marine Corps is part of the Navy Department and the Space Force is standing up under the Air Force) aren’t the whole budget.
But the military departments together do not comprise the entire defense budget. A huge portion of their spending exists outside departmental budgets for health care, allowing further obfuscation of what each military branch actually spends.
Still, comparing the uniformed service spending to an account fast-approaching the size of a standalone branch is helpful, namely defense-wide spending. From the Missile Defense Agency to Special Operations Command to Washington Headquarters Service, the so-called Pentagon “fourth estate” essentially refers to all of the entities within the Defense Department that are considered enterprise-wide. This ranges from administrative and support functions like human resources to combat enablers like the Defense Intelligence Agency (DIA) and DARPA.
Unlike the military services, the fourth estate resembles a loosely affiliated patchwork of semi-autonomous agencies. This spending accounted for nearly one-fifth of the defense budget in the 2020 request.
As House Armed Services Committee Ranking Member Mac Thornberry has noted, these agencies contain up to about a quarter of the Pentagon’s workforce — nearly half of its civilian personnel—and control a contractor army estimated at 600,000 people.
How does adding these costs in impact the numbers?


Eaglen goes through much more analysis, noting that there are many additional controversies. How does one count the large part of the intelligence community that’s nested under the Air Force? How about the Marine Corps?
Her conclusion is sensible:
All of the arguments are hotly contested—both within and between the services and do not account for every consideration that policymakers must weigh against the demands of the wider strategic environment facing the US military in the coming decade. Even so, it’s important to create a shared baseline. For analysis and potentially decision-making to shift these investments in the future based on a forthcoming joint warfighting concept.
Ultimately, each service can have their own set of numbers, but this does little to help make a decision. As the pressure mounts for senior Pentagon leaders to defend their respective priorities during the budget debates of fiscal year 2021, Congress must be presented with accurate information. Carve out everything or carve out nothing. Congress, and the Pentagon, should be working with the same set of facts.
But, as I’ve already noted, picking which set of numbers one uses slants the debate to the advantage of some services/enterprises and the disadvantage of others. Which numbers one uses really depends on what question you’re trying to answer. One size does not fit all.
Beyond that, “Who gets what share of the pie?” shouldn’t even be the question we’re trying to answer. Rather, we need to ask “What capabilities does the nation need the Defense Department to provide and in what capacity?” This, in turn, leads to more questions. Regardless, the debate shouldn’t be about a “fair share” of the pie.









