The Air Force’s new Sentinel intercontinental ballistic missile (ICBM) program is so massively over budget and behind schedule that it must be bailed out by Defense Secretary Lloyd Austin before July 9 or face termination. In either case, U.S. nuclear forces would remain sufficient to deter any adversary, including Russia and China, from a nuclear strike. Termination of Sentinel, however, would make the country much safer while saving taxpayers hundreds of billions of dollars.
For Congress and the Biden administration, this should be a no-brainer. It is time to cancel this expensive, unnecessary, and dangerous program.
Expensive
The Sentinel program was established in 2020 with a sole-source bid from Northrop Grumman, at a projected cost of $95 billion—already $30 billion more than the first cost estimate by the Air Force in 2015. In January, the Air Force revealed that the estimated cost had passed $131 billion, a 37 percent over the 2020 estimate. The new ICBM is still being developed; thus far, not a single missile has been produced.
That $131 billion covers the development and acquisition of the missiles, but it is not the full picture. It does not include their nuclear warheads, which are expected to cost $15 billion. Nor does it include the cost of operating and maintaining the missiles over their anticipated 50-year lifetime. Air Force officials have yet to release an estimate for that figure, but historical data on the current Minuteman III ICBM suggests it would be about $100 billion in today’s dollars.
In January, the Sentinel program triggered a review under the 1982 Nunn-McCurdy Act, which requires the Pentagon to notify Congress if a weapon’s per-unit cost (either procurement alone or the development, procurement, and construction total) goes 25 percent over its most recent estimate or 50 percent over the original one. Under Nunn-McCurdy, Sentinel’s projected increase of 37 percent constitutes a “critical breach.” When a critical breach occurs, the law requires the program to be terminated––unless the Defense Secretary certifies that it is essential to national security and that there are no reasonable alternatives.
Unnecessary
Secretary Austin is likely to claim that there is no alternative, that the United States needs ICBMs for its nuclear deterrent, as long argued by the Air Force and Strategic Command. In February, STRATCOM commander Gen. Anthony Cotton insisted to the Senate Armed Services Committee that the new ICBM program “absolutely has to be done.”
But there is an alternative: just rely on the rest of America’s nuclear arsenal. As Gen. Cotton’s predecessor, Adm. Charles Richard, told lawmakers in 2021, the nuclear arsenal is designed to operate and meet all presidential objectives even if one leg of the “nuclear triad” no longer exists. The U.S. typically has eight to 10 ballistic missile submarines deployed at sea, each carrying 20 missiles and about 100 warheads, enough to devastate a country. Unlike ICBMs, U.S. ballistic submarines are undetectable and therefore invulnerable to an enemy first strike. Air Force bombers—the B-52s that are getting a thousand new stealthy nuclear-capable cruise missiles and the 100 B-21s that will join them—can be launched on warning of incoming attack and recalled if necessary.
If more nuclear warheads are deemed necessary in the near term, today’s Ohio-class submarines, whose missile loadouts were reduced to comply with the New START Treaty, could carry about 800 more warheads than they do today—twice as many as currently carried by U.S. ICBMs. In the longer term, the Pentagon could add to the planned 12 next-generation Columbia-class missile submarines or build more B-21s and cruise missiles for a fraction of Sentinel’s cost.
Dangerous
ICBMs sit in fixed, in-ground silos visible from space. Adversaries know exactly where they are. Sentinel proponents call this a virtue for two reasons.
First, they say these missile fields increase deterrence by raising the cost of a first nuclear strike on the U.S. homeland: they argue that an adversary would need to expend a large fraction of its nuclear arsenal to wipe out all 450 silos. This line of reasoning ignores the submarines, which could mount a counterattack no matter how many land-based missiles are destroyed.
Moreover, an attack on this “nuclear sponge” would incur horrific human costs. Millions of Americans living in ICBM-host states—Colorado, Montana, Nebraska, North Dakota, and Wyoming—would be subject to lethal fallout. Depending upon the direction of the wind, virtually everyone in the continental United States, Canada, and northern Mexico would be at some risk of receiving a lethal dose of radiation. (If Sentinel is not cancelled, Congress and the administration should at least require and release a full assessment of the potential effects of attacks on the ICBM silos.)
Second, proponents say the ICBM force is the “most responsive” leg of the triad because it is kept on a hair-trigger posture, lest it be wiped out in an enemy first strike. Again, this ignores the submarines, which stand no less ready.
This attempt to make a virtue of vulnerability also ignores the terrible risk that these missiles might be launched by mistake. When warned of an incoming strike, the president has only about seven minutes to decide whether to launch the ICBMs. This leaves very little time for deliberation or verification of the attack. In the past, there have been mistaken alerts of incoming nuclear attacks that could have triggered a U.S. launch.
Currently, neither the House or Senate Armed Services Committees are planning hearings on the Sentinel cost overrun or on alternatives to proceeding with the program. The Bicameral Nuclear Weapons and Arms Control Caucus therefore plans to hold an unofficial hearing in July. The Armed Services Committees and the administration too should consider the alternatives instead of charging blindly ahead. We believe that they would find canceling Sentinel is the only reasonable path to reducing the risk of accidental nuclear war and cutting back the endless spiral of increasing nuclear costs.
Dr. Sébastien Philippe is a Research Scholar in the Program on Science and Global Security at Princeton University.
Sharon K. Weiner is an Associate Professor at the School of International Service, American University and a visiting researcher at the Program on Science and Global Security, Princeton University.
Frank N. von Hippel is a senior research physicist and professor of public and international affairs emeritus with Princeton’s Program on Science & Global Security.
