An artist's conception of the Sentinel ICBM.
“Struggling”—that’s the word Air Force Secretary Frank Kendall used in December to describe one of his service’s biggest and most important modernization projects.
The program is Sentinel, the long-overdue effort to replace intercontinental ballistic missiles that first became operational over 50 years ago.
The U.S. nuclear deterrent consists of three types of weapons—ICBMs, ballistic missiles launched from submarines, and bombers carrying cruise missiles or gravity bombs.
The logic of having three distinctly different ways of retaliating against nuclear aggression has been endorsed by three generations of policymakers and scholars, not because the U.S. intends to fight a war but because Washington needs to convince adversaries that it can, if necessary, after suffering a surprise attack.
In the absence of effective defenses, it is the threat of overwhelming retaliation that dissuades an enemy from attacking in the first place.
But America’s strategic deterrent has grown decrepit with age. Ballistic missile subs will begin retiring later in this decade. The B-52 bombers that will carry air-launched nuclear weapons until a new bomber becomes operational were last built in 1962.
And then there is Minuteman III, the land-based ballistic missile that Sentinel is supposed to replace. Minuteman III has been around for so long that its booster engines, reentry vehicles, warheads and guidance systems have all gradually been replaced. In some cases, more than once.
The Air Force, which owns and operates the system, is adamant the Minuteman III is too old to have its service life extended further. It needs to be replaced, starting around 2030.
Apparently, that now is not going to happen. Tony Capaccio of Bloomberg News reported earlier this week that the cost of the program has increased from its baseline by 37%, and that its initial operating capability has slipped by two years.
It will probably be delayed longer than that, into the mid-2030s, even as the Minuteman III force becomes less dependable.
It was also Tony Capaccio who broke the story four years ago that the total life-cycle cost of the Sentinel effort through 2075 was estimated to be $264 billion—an estimate that now looks way too low.
Air Force Under Secretary Kristyn Jones told a Washington audience this week that the new missile, being developed by Northrop Grumman
These facilities are all located underground, scattered across five sprawling bases and seven states in the upper Midwest.
Rebuilding the ICBM launch infrastructure will be by far the Air Force’s biggest civil works project in recent times, and it is increasingly clear the service doesn’t know for sure how much time it will take or what it will cost.
However, there are reasons to doubt that the silos and launch centers are the only problematic aspects of the project. The Government Accountability Office’s most recent assessment of Sentinel identified several sources of concern:
- Shortfalls in hiring and clearing key staff
- Disruptions in the supply chain for essential inputs
- Delays in construction of software testing facilities
- Deficient planning tools for project management
Such problems are not uncommon in complex weapons projects, especially during the early years, but Sentinel is working against a deadline because the missiles that must be replaced are aging out. They’ve been in the ground for half a century, which is well beyond their originally expected service life.
Adam Smith, ranking member on the House Armed Services Committee, describes the recent revelations of cost growth and schedule delays as “alarming,” and with good reason: ICBMs play a crucial role in the overall scheme for deterring nuclear war.
U.S. nuclear posture reviews have repeatedly raised the possibility that adversaries such as China might someday develop a means for tracking U.S. ballistic-missile subs when they are submerged.
While that prospect seems remote today, if it were to occur ten years hence and the ICBM leg of the nuclear triad was impaired by delays and cost overruns, an attacker could greatly degrade the U.S. nuclear force by taking out a mere handful of targets—a dozen subs, two sub bases, and three or four bomber bases.
In such a scenario, the 400 ICBMs sitting in hardened silos would become critical to deterring a surprise attack. In fact, the U.S. might need more than 400 ICBMs to cope with the combined nuclear firepower of Russia and China—China already has more missile silos than the U.S. does.
If this scenario seems fanciful to you, then you aren’t thinking the way nuclear planners do. We can’t know the precise circumstances in which a future nuclear crisis might unfold, but what we do know is that when that day arrives, foreign adversaries must have no doubts about America’s ability to retaliate if they launch a first strike.
