As part of the United States’ long-overdue effort to modernize its aging nuclear arsenal, the Air Force is developing the Ground-Based Strategic Deterrent (GBSD) to replace the 400 Minuteman III intercontinental ballistic missiles (ICBMs) deployed across the United States. Critics have characterized the land leg of the triad as too costly or unsafe, and propose alternatives to the GBSD ranging from extending the lives of the Minuteman III ICBMs, to delaying the GBSD, to eliminating the land leg of the triad altogether.REF

However, replacing the Minuteman III fleet by the end of the decade is necessary to avoid severely eroding U.S. strategic deterrence, as ICBMs play a critical role in maximizing the costs of an adversary attack. Fielded in 1970 with an intended lifetime of only 10 years, the Minuteman III missiles are so old that a failure to replace them, or even a further delay, will result in a missile force unable to meet deterrence requirements as it continues to age and is forced to dwindle in numbers over time.REF The Biden Administration must support, and Congress must provide, full funding for the GBSD program to ensure an on-time delivery at the end of the decade.

Why It’s Dangerous

Failing to deliver the GBSD by the end of the decade, when the Minuteman III ICBMs are set to retire, would result in unilateral reductions of the U.S. ICBM force. Such an outcome for the U.S. ICBM force is dangerous because it:

Significantly Erodes U.S. Nuclear Deterrence.

• Eliminating ICBMs simplifies adversary targeting. The scale and precision required to stage a successful attack against the U.S. fleet of 400 hardened and dispersed ICBMs is prohibitive.REFEven if attempted, such a blitz would deplete enemy forces and invite severe retaliation, which is why General John Hyten, Vice Chairman of the Joint Chiefs of Staff, called a strike on the U.S. homeland “almost an impossible decision to make” for any adversary.REF Russia is the only nuclear state that can overcome the U.S. ICBM arsenal, but doing so would either require Russia to use over 400 of its highest-quality weapons or choose to gamble that the United States will not retaliate before it strikes the homeland. Both options are extremely risky. Eliminating ICBMs would drastically simplify adversary planning for Russia and other nuclear states, like China, as they would only need to launch a small-scale attack against a few bomber bases, submarine ports, and command centers in a first strike, making a pre-emptive strike less costly and more appealing.REF
• ICBMs’ responsiveness provides an effective means to hold adversary targets at risk. Because ICBMs are always on alert and can strike adversary targets within minutes of a presidential order, the land leg helps to convince adversaries that an attack will be met with immediate retaliation. ICBMs’ accuracy, range, yield, and speed enable the United States to threaten targets around the world, and the GBSD will improve these capabilities.REF This responsive option complements the survivability and flexibility provided by the sea and land legs of the triad, and the United States would be worse off without a prompt response capability that can disrupt enemy attack and deter a number of strategic threats.
• Retiring ICBMs and relying only on the sea leg of the triad for daily deterrence is extremely risky. Since nuclear bombers are not on alert, eliminating ICBMs would leave the United States with a monad of nuclear submarines to deter Russia’s and China’s vast arsenals of land-based, sea-based, and air-based strategic and non-strategic nuclear delivery systems. As General Hyten argued, that would place the United States “basically an intelligence failure or a technical failure away from losing the entire structure.”REF For example, Russia and China could figure out how to detect U.S. ballistic-missile submarines (SSBNs) within the next 50 years. Such a breakthrough would not be inconceivable, especially since eliminating the U.S. ICBM threat would enable Russia and China to invest in anti-submarine warfare instead of capabilities aimed at destroying or defending against the ICBM force.REF In fact, both the 2010 and 2018 Nuclear Posture Reviews cited this dangerous possibility.REF Opponents argue that ICBMs are redundant, but they are not; each leg of the triad is designed to bring a unique deterrent value, as together, they complement one another to hedge against technical failures and inherent flaws in the others.REF
• Erodes Allies’ Confidence in U.S. Extended Deterrence Commitments. The United States extends its nuclear umbrella to more than 30 allied countries, which view the U.S. effort to sustain a strong nuclear triad as a reflection of U.S. extended deterrence commitments. Allowing one leg of the triad to atrophy or eliminating it entirely would certainly cause some U.S. allies to question the U.S. commitment to defending them. With their ability to hold at risk precise targets of interest, ICBMs contribute to the credibility of the nuclear triad, which provides the backstop for U.S. theater deterrence.

Why Critics’ Arguments Are Unfounded

The following are rebuttals of the most-often-used arguments made by critics of modernizing U.S. ICBMs:

The GBSD Is Not Too Costly. The approximately $95 billion price tag for total GBSD acquisition costs over the next decade looks big—and it is—but investing in GBSD now will save costs in the long run. A 2014 analysis estimated that acquiring the GBSD will cost less than further maintaining the Minuteman III fleet, which would also not meet long-term warfighter requirements.REF Once the GBSD is fielded, the ICBM force is actually the least expensive to maintain compared to the land leg and sea leg of the triad.REF A program lasting through the 2070s that contributes so significantly to nuclear deterrence, the Department of Defense’s number one priority for national security, is certainly affordable.

ICBMs Are Not on Hair-Trigger Alert. ICBMs’ responsiveness does not equate to being just a breadth away from launch; it means that adversaries know that the United States can respond quickly to an attack.REF With multiple redundant physical and procedural safeguards required for launch, ICBMs are extremely safe. In fact, such required safeguards can maximize policymakers’ threat assessment and decision time. A host of sensors, radars, and satellites also apprise decision-makers of adversary activities, making a launch on a false alarm improbable. As General Kevin Chilton, former Commander of U.S. Strategic Command (STRATCOM), explains, “People who described our ICBMs as being on ‘hair-trigger’ alert either do not know what they are talking about or are intentionally attempting to frighten the uninformed into calling for the de-alerting of the ICBM leg.”REF

Extending Minuteman III Is Not Viable. Admiral Richard made it very clear that “[y]ou cannot life-extend Minuteman III” any further.REF The Minuteman III has already been life-extended more than 50 years beyond its intended lifetime. As early as 2006, an Air Force assessment of options for further extending the Minuteman III concluded that the missile does not meet post-2018 warfighter requirements—and that was before the geopolitical situation worsened to today’s dangerous environment.REF Last year, the Government Accountability Office found that Air Force officials will begin to lose confidence in the complete Minuteman III fleet after 2026.REF As General C. Robert Kehler, former STRATCOM Commander, remarked, “Further delay is unacceptable—it’s time to move out on a new ICBM.”REF

Forgoing the GBSD replacement and maintaining the Minuteman III missiles still means that they will gradually retire, leaving the U.S. with fewer and fewer ICBMs. Such a unilateral reduction in forces would eliminate any negotiating leverage that the U.S. would have for future arms control discussions. As Senator Deb Fischer (R–NE), the Ranking Member of the Senate Armed Services Subcommittee on Strategic Forces, aptly pointed out: “Why would our competitors agree to new rounds of arms reductions if they knew the U.S. was cutting its forces anyway, regardless of whether they agreed to do the same?”REF

What Key U.S. Senior Leaders Say

Key figures ranging from Obama Administration appointees to senior military leaders, and even to newly appointed Biden Administration officials, have maintained strong bipartisan support for fielding the GBSD to sustain the land leg of the nuclear triad.

• President Obama’s Secretary of Defense Ash Carter, when addressing the Minuteman III ICBMs, stated that “there comes a time when something that old needs to be replaced. And we have put those dates off…to the point where we really need to move out on those programs.”REF
• Robert Scher, President Obama’s Assistant Secretary of Defense for Strategy, Plans, and Capabilities, explained, “The ICBM leg…is the most responsive of the legs and ensures that no adversary can believe that they have a strike that immediately eliminates all of our capabilities to respond.”REF
• Admiral Charles Richard, STRATCOM Commander, stated, “Eliminating our ICBM capability, and specifically the GBSD, would be dangerously provocative, present a less credible strategic threat, and grant adversaries a vastly reduced target set—raising the risk to our Nation of a disabling first strike.”REF
• Deputy Secretary of Defense Kathleen Hicks expressed her support for the GBSD, stating that “[s]ingle warhead ICBMs contribute to stability” and that she believes “our deterrent is strongest as a triad.”REF

Recommendations for the U.S.

The Biden Administration should:

• Fully support the GBSD in the President’s budget request for fiscal year 2022 and the Future Years Defense Program. The budget should support the Department of Defense’s plan to achieve GBSD initial operating capability by 2029.

Congress should:

• Sufficiently fund the GBSD to ensure on-time delivery by the end of the decade. Congress should avoid paring back this program to the lowest level of funding possible, and instead seek to minimize risk in the development schedule.

Patty-Jane Geller is Policy Analyst for Nuclear Deterrence and Missile Defense in the Center for National Defense, of the Kathryn and Shelby Cullom Davis Institute for National Security and Foreign Policy, at The Heritage Foundation. Dangerous Nuclear Policy Ideas is a series of Issue Briefs on existing nuclear policy proposals that would, in fact, weaken America’s national security. Elizabeth May, a member of The Heritage Foundation’s Young Leader’s Program, provided invaluable assistance in the production of this report.