America’s most advanced weapon has been defeated by concrete. The LGM-35A Sentinel, the country’s next-generation intercontinental ballistic missile (ICBM), is a fiscal and logistical disaster. Its failure reveals a deep rot in the Pentagon’s planning, forcing a dangerous gamble on a missile system built when The Beatles were breaking up. The problem was not the rocket science. It was the construction work.
The financial scale of the debacle is vast. In January 2024 the Sentinel programme’s unit cost had soared by 37%, triggering a “critical” breach of the Nunn-McCurdy Act, a law meant to curb runaway military spending. By July the Pentagon’s own cost-assessment office projected the total bill would reach nearly $141 bn. That is an 81% increase over the 2020 baseline. An efficient upgrade has become a black hole for taxpayer money.
The missile itself saw only minor cost growth. According to Andrew Hunter, the Air Force’s top buyer, the real culprit was the “command and launch” segment—the sprawling network of silos and command centres. This was the responsibility of Northrop Grumman, the sole contractor after its rival Boeing withdrew from the bidding. Representative Adam Smith, a senior Democrat on the House Armed Services Committee, has called the oversight “gross malfeasance” by both the contractor and the Pentagon. Planners focused on the warhead, and forgot about the hole in the ground.
This oversight stemmed from a single, flawed assumption: that the new system could be slotted into the old one’s footprint. The Air Force believed it could reuse infrastructure from the Minuteman III, the missile Sentinel is meant to replace. It planned to use thousands of miles of existing communications cables. Then it discovered the 1960s-era wiring lacked the bandwidth for a 21st-century weapon. It required a complete, and costly, replacement.
As Air Force officials later admitted with considerable understatement, the initial cost assumptions “were just not particularly valid.” The consequences are now measured in years of strategic risk.
The miscalculation ran deeper. The military assumed it could simply excavate and refit the old Minuteman III silos. But the new Sentinel missile and its support equipment are “significantly bigger” than their predecessors. The old silos were too small. The plan was scrapped in favour of building entirely new ones across five states, turning a weapons upgrade into one of America’s largest-ever civil-engineering projects. As Air Force officials later admitted with considerable understatement, the initial cost assumptions “were just not particularly valid.”
The consequences are now measured in years of strategic risk. Sentinel’s initial operational capability has slipped from 2029 to the early 2030s. Its first flight test is delayed until at least March 2028. This forces America to rely on the Minuteman III, a missile first deployed in 1970, until as late as 2050. That is 14 years longer than its last life-extension programme intended.
This delay is not happening in a vacuum. Russia is deploying new ICBMs, and China is rapidly expanding its own silo-based missile force in the desert. The Sentinel was meant to be America's answer to this modernisation. Instead, its shambolic progress opens a potential window of vulnerability. It forces America to rely on a geriatric deterrent while its rivals field new ones.
Keeping the Minuteman III on watch for an extra decade and a half is a profound wager against decay. The system will be 80 years old at its planned retirement. Sustaining a weapon for another two decades past its intended lifespan presents immense challenges, from sourcing scarce electronic parts for 1970s technology to maintaining the morale and expertise of the crews who operate it. The Pentagon has not budgeted for this emergency life support, because it never believed it would be necessary.
To be sure, some argue that the system, however clumsy, is working. The Nunn-McCurdy breach forced a reckoning. The Pentagon is restructuring the programme, with a new plan expected by the end of this year. A recent Government Accountability Office report even framed the crisis as an “opportunity” to fix the programme’s fundamental flaws. This, the argument goes, is not a cover-up but a painful, public correction.
But this mistakes the symptom for the disease. A process that identifies an 81% cost overrun only after contracts are signed and ground is broken is not a success; it is a systemic failure. Calling such a fiasco an “opportunity” is the sort of bureaucratic euphemism that papers over profound weakness. The extended reliance on the Minuteman III is not a planned overlap. It is an emergency measure born of a colossal planning blunder.
The Sentinel saga is an indictment of the Pentagon’s acquisition culture. It fetishises the advanced weapon—the fighter jet, the stealth bomber, the missile—while treating the infrastructure that supports it as a tedious afterthought. It is brilliant at designing warheads, but incompetent at pricing construction jobs. The greatest threat to America's deterrent is not a foreign missile, but a domestic spreadsheet.
