The Department of Defense is again facing mounting evidence that its weapon systems acquisition process is structurally incapable of delivering major programs on time or within budget. New findings from multiple Government Accountability Office assessments show that cost growth, schedule delays, and immature technologies remain embedded across the Pentagon’s largest portfolios.
GAO’s 2025 annual assessment reports that the costliest weapon programs collectively increased their projected costs by $49.3 billion, with the Air Force’s Sentinel missile program alone responsible for more than $36 billion of that growth. These overruns occurred even as the Department attempted to use newer Middle Tier of Acquisition pathways intended to accelerate development. Instead, GAO found that many programs using these rapid pathways still relied on immature technologies and experienced delays.
The structural issues extend beyond individual programs. GAO’s 2024 assessment shows that the average major defense acquisition program now requires more than a decade to deliver even an initial operational capability. This trend has worsened over time, despite reforms designed to speed development. GAO concluded that slow, linear development approaches continue to dominate, and only a small number of programs plan to fully adopt leading commercial product‑development practices.
Earlier assessments reinforce the same pattern. GAO’s 2023 review found that more than half of the major programs examined reported new delays, driven by supplier disruptions, software development problems, and quality‑control deficiencies. The report also highlighted that programs continue to make investment decisions without sufficient technical knowledge, increasing the likelihood of later cost and schedule failures.
Across all three years of assessments, GAO repeatedly emphasized that weapon systems acquisition remains on its High Risk List. The consistent findings point to a systemic problem: programs are routinely approved and funded before requirements are stable, technologies are mature, or designs are validated. Once billions are committed, the Department becomes locked into long, inflexible development cycles that are difficult to reverse.
The result is a portfolio of weapon programs that cost more, take longer, and deliver less capability than planned, leaving the United States with aging systems in the field while adversaries iterate faster. GAO’s findings indicate that without enforcing knowledge‑based decision points, adopting iterative development practices, and tying funding to demonstrated progress, the Department will continue to spend billions without achieving the speed or innovation it seeks.
Sources
- GAO