Is it time to kick out one leg of the nuclear triad?

The intercontinental ballistic missile (ICBM) has been a pillar of the United States’ nuclear deterrent since the first ICBM was deployed in 1959. Initially, the ICBM was imperative, as it guaranteed that the U.S. possessed the ability to respond to and to deter attacks during the Cold War. Despite this historic nostalgia, however, the current fleet of 400 deployed Minuteman III ICBMs is not only a redundant part of the U.S. nuclear triad—now consisting of ICBMs, ballistic missile submarines, and strategic bombers—but a potential liability that risks unwanted escalation and turns wide swaths of the continental United States into counterforce targets.

The ICBM used to serve as an important hedge during the Cold War, guaranteeing the survivability of the U.S. nuclear deterrent at a time when the air-based leg required airspace penetration and sub-launched ballistic missiles had shorter range and less accuracy than ICBMs. Today, however, it is safe to scrap the nuclear triad and move to a dyad consisting of only air and sea legs. Clearly, the air and sea legs of the U.S. strategic forces are a sufficiently redundant deterrent posture, while the ICBM fleet provides little added deterrence, but with costly strategic and fiscal drawbacks.

Oh, and ICBMs are expensive. The Obama administration signed off on a modernization program for the aging ICBM fleet that is now projected to cost as much as $140 billion over the next 30 years in order to procure a next-generation ICBM, dubbed the ground-based strategic deterrent (GBSD), and another $150 billion to operate and sustain the GBSD. Let’s address why this price tag is nearly criminal, and why unilaterally eliminating the ICBM fleet makes good sense not just fiscally but also from the standpoint of nuclear strategy.

First and foremost, deterrence in the strategic realm simply requires that the U.S. maintain the ability to inflict unnecessarily high costs on adversaries in response to aggression by possessing a secure second-strike capability. The sea-based leg of the triad, consisting of 12 SSBN Trident II D5 ballistic missile submarines, is sufficient on its own to deter attacks. This will remain the case far into the future given that it is exceedingly difficult to locate and destroy a single SSBN, and all but impossible to eliminate all of the SSBNs deployed at a given time before they unleash salvos of the 20 Trident II sub-launched ballistic missiles each is carrying.

With each Trident II capable of carrying multiple independently targetable re-entry vehicles, and with each of these warheads packing a punch of up to 455 kilotons, low-end estimates posit that each SSBN is capable of 500 times more damage than the bomb dropped over Nagasaki. The invulnerability of the sea-based component of the U.S. nuclear deterrent is further guaranteed far into the future considering the expansive modernization program that the submarine fleet is undergoing. In short, there is no rational argument for maintaining the ICBM fleet due to fears of SSBN vulnerability now, or far into the future.

While the sea leg of the nuclear triad is a sufficient deterrent on its own, the air leg consisting of nuclear-capable strategic bombers provides more than enough redundancy to leave no plausible scenario in which the U.S. would be vulnerable to a disarming first strike counterforce campaign. The air leg consists of a multitude of diverse ways to deliver nuclear payloads such as B-2 stealth bombers carrying penetrating gravity bombs to B-52 bombers carrying multiple standoff range nuclear tipped air-launched cruise missiles. The air-based leg is also undergoing significant modernization, manifesting itself in near-future complexes such as an upgraded stealth bomber capable of deploying an upgraded stealthy air-launched nuclear standoff cruise missile. It is extremely difficult to envision a scenario in which integrated air and cruise missile defense environments become so impermissive that the air-based leg can’t be counted on to deliver a nuclear response. As such, it would be indescribably irrational for an adversary to launch a nuclear first strike against the U.S., with or without an ICBM fleet.

Along with being redundant, the ICBM portion of the triad is also the most dangerous. This revolves around the U.S. launch posture and the “use or lose” nature of the fixed-location silo-based fleet of ICBMs. If U.S. early warning radars detect a launch from an adversary, the President has but minutes to decide whether to launch an ICBM salvo or risk losing them to a disarming first strike. This launch on warning posture, as its known, is dangerous for obvious reasons. There have been multiple occasions where America’s early warning architecture detected massive launches that turned out to be false alarms. As previously alluded to, the fixed location nature of the ICBM fleet means that the President may feel immense pressure to use or lose the ICBMs in such a contingency.

One common rationalization in defense of the ICBM fleet is the “warhead sponge” argument that posits that the ICBM fleet is necessary as a cost imposing strategy given that adversaries would need to dedicate hundreds of warheads for counterforce that would otherwise be free to target countervalue population hubs. This argument is misguided for a few reasons. Most obviously, why would U.S. strategists guarantee that wide swaths of the continental U.S. eat nuclear warheads by providing 400 high-priority targets to lob nukes at? Absent the ICBM fleet, counterforce targets in the U.S. are limited to command and control nodes, two SSBN bases, and three strategic bomber bases.

The logic of the “warhead sponge” argument is further questioned when one considers that adversaries are potentially incentivized to preemptively limit damage by targeting American ICBM silos first if they feel as though a conflict is escalating uncontrollably. To elaborate, if an adversary feels as though a conventional conflict is spiraling out of control, they may calculate that its in their interest to massively attack the U.S. ICBM fleet, given its combination of firepower and vulnerability, a temptation that wouldn’t exist without ICBMs. Even if the “warhead sponge” logic was to be accepted, we’re still left without explanation as to why taxpayers should eat a $140 billion price tag for a fancy new ICBM if its raison d’être is to be a warhead magnet in a catastrophic missile exchange.

Lastly, the argument that ICBMs provide the President with a quicker response option than other means of delivering strategic warheads has been refuted considering there is no operationally significant difference between the effort to launch an ICBM salvo versus that of a Trident II SSBN. Moreover, in stark juxtaposition to the days of the Cold War, ICBMs are now less accurate than Trident II sub-launched ballistic missiles.

One last common argument in defense of the ICBM fleet is that they are necessary given their counterforce capability. Without ICBMs, and even without reallocating the disassembled Minuteman III strategic warheads elsewhere in compliance with New START, the U.S. would maintain formidable ability to hold counterforce targets at risk. The combination of air and sea-based strategic platforms, as well as tactical nuclear weapons and conventional strike capabilities, the latter of which are significantly more lethal as tools of counterforce compared to the days of the Cold War, is more than sufficient to satisfy counterforce targeting needs.

All of these points are augmented by the fact that the only plausible adversary the U.S. can use ICBMs against is Russia (a declining regional power with an economy the size of Belgium’s and the Netherlands’ put together) considering ICBM flight trajectories to every other feasible target would have to pass through Russian territory. The implications of this are that the ICBM fleet does not add deterrence considering these countries know that the U.S. wouldn’t risk nuclear escalation with Russia by launching an ICBM salvo.

All things considered, forcing taxpayers to pay for an expensive new ICBM is misguided. Not only will a new ICBM be an unnecessary expenditure, it will also potentially impact nuclear stability given the new capabilities it is expected to possess and how adversaries read U.S. intentions from them. While outside of the scope of this piece, ICBM elimination (or simply cuts) could also be done within the context of arms control negotiations so as to extract concessions from nuclear adversaries.

Policymakers would be wise to seriously consider the strategic necessity of, at bare minimum, spending well over $100 billion to modernize the ICBM fleet when other more cost effective solutions to maintain an ICBM fleet exist. Preferably, they would consider whether it is necessary to deploy ICBMs period. Strategic stability and taxpayers’ pockets would be the biggest beneficiaries of doing away with this Cold War relic.

Alex Moore holds a Masters degree in International Conflict and Security from the Brussels School of International Studies in Brussels, Belgium. He can be found on Twitter @Moore_Alex01.