The scales have tipped. The script has flipped. The tables have turned. When the Congressional Budget Office (CBO) published its monthly budget review last week, it reported that in Fiscal Year 2024, for the first time, the United States spent more on interest payments to service the national debt than on the military.

In FY2023, the Pentagon budget was $776 billion, while net interest on the public debt was $710 billion. Preliminary numbers for FY2024, which ended September 30^th, tag Pentagon spending at $826 billion, while net interest on the public debt rose to $950 billion, a 34 percent jump.

The problem here is pretty self-explanatory: money spent servicing debt cannot be spent on other priorities, and that includes the military. And if interest payments continue to grow as a percentage of the total budget, this problem will only get worse. In other words, the spiraling national debt is a national security threat because it imperils the future availability of funds for the military.

Pentagon spending is the largest driver of the national debt in the discretionary budget by a landslide, so it doesn’t take a budget analyst to see that reining in excessive Pentagon spending should be a national security priority. But try telling that to Congress and the Pentagon.

As Congress gears up for a post-election budget showdown, the debate over the Pentagon’s topline has been pigeonholed into a question of whether to spend a little more or a lot more than last year. In the House, lawmakers took the relatively more responsible approach by adhering to budget caps agreed to last year. Caps that provided for a 1 percent increase in defense spending compared to FY2024. Senate appropriators on the other hand proposed an additional $21 billion for the Pentagon, which they characterized as “emergency funding” in order to circumvent the budget caps. As we’ve written about before, much of that spending is not responding to actual emergencies—it really is just about sidestepping the caps to boost the Pentagon’s topline.

Setting aside “emergency” distinctions, between the House and Senate, lawmakers proposed over $39 billion in program increases to the FY2025 Pentagon budget request just for Procurement and Research, Development, Test and Evaluation (RDT&E). About 72 percent of those program increases were for projects the Pentagon sought zero dollars for, what we call Zero to Hero increases.

At the same time, policymakers at the Pentagon are pressing ahead with sweeping modernization plans that promise to break the bank even before accounting for their current and future cost-growth. Take, for instance, the Sentinel ICBM program. After the program’s cost ballooned by 37 percent earlier this year, we called for its cancellation. Instead, after reevaluating the program, the Pentagon certified it to continue—but under a restructured program that is now projected to cost 81 percent more than anticipated. In May, we published a report digging into the Sentinel and its strategic underpinnings and concluded, as many others have, that the land-based leg of the triad is not necessary for deterrence. So not only is this program 81 percent over budget, it’s also strategically irrelevant.

Advocates of increasing military spending will tell you that our national security depends on it, when in fact it depends on the opposite. They’ll concede that the national debt is a problem, but they won’t ask the Pentagon to be part of the solution. It’s a dangerously short-sighted approach. Beyond helping to rein in the debt, a fiscally responsible approach to military spending would require the Pentagon to think through its strategies and programs and decide which are best suited for the world we now live in. This exercise in strategic prioritization would help the Pentagon focus on the things that matter most, while allowing it to step back from programs and strategies that distract and detract from the essentials. As far as we’re concerned, that’s just common sense.