The United States’ LGM-35A “Sentinel” intercontinental ballistic missile programme has become an expensive and embarrassing reminder that money alone cannot buy strategic certainty. Air Force Global Strike Command chief Gen. Stephen Davis publicly praised Sentinel’s “digital” capabilities on 27 January, even as cost overruns and schedule slippage have left the project in jeopardy and prompted an official breach of US procurement law.
What began as a straightforward replacement for the Cold War‑era Minuteman III has morphed into a sprawling procurement fiasco. The Pentagon’s cost office now estimates total acquisition costs could reach about $140.9 billion—an 81 percent increase over original estimates—and the programme triggered a Nunn‑McCurdy breach in 2024. Years of reorganisation have not resolved disputes between Northrop Grumman and the Air Force over schedules and requirements, leaving the programme’s timeline “unclear,” in the commander’s own words.
The proximate cause of much of the overrun is prosaic: ground infrastructure. Planners initially hoped to reuse existing Minuteman III silos, but decades of wear and incompatible designs forced a rethink. The service now plans roughly 400 new hardened missile silos across five states, a task that entails land acquisition, environmental reviews, heavy civil construction and a host of digital and power upgrades—work that has proved slower and costlier than anticipated.
That construction headache carries strategic consequences. If Sentinel cannot assume the ground‑based leg of the nuclear triad by the early 2030s, the Air Force faces a stark choice: retire Minuteman III missiles on schedule and risk a temporary degradation of land‑based deterrence, or extend the life of an ageing force. Washington is already discussing stretching Minuteman III service lives toward 2050, a stopgap that would leave the United States reliant on increasingly obsolete hardware.
The Sentinel debacle is more than a single procurement failure; it highlights deeper frictions in the US defence ecosystem. High costs reflect not only contractor performance but also an industrial base that struggles with large civil works, a complex regulatory environment, and ballooning sustainment costs for legacy systems. Meanwhile, potential adversaries are modernising their arsenals and demonstrating rapid silo construction, intensifying pressure on US planners to preserve credibility.
For Washington, Sentinel is both a budgetary and a reputational problem. Congress will face hard choices about whether to pour still more funding into a faltering programme or to rebalance investments across the triad and other deterrent measures. In the near term the United States can lean on sea‑ and air‑based forces, but a prolonged vulnerability in the ground leg would complicate deterrence calculations, arms‑control diplomacy and strategic signalling to Moscow and Beijing.