To continue to field a nuclear force roughly the same size as it is today, the United States plans to modernize virtually every element of that force over the coming decades. CBO estimates that the most recent detailed plans for nuclear forces, which were incorporated in the Obama Administration’s 2017 budget request, would cost $1.2 trillion in 2017 dollars over the 2017–2046 period: more than $800 billion to operate and sustain (that is, incrementally upgrade) nuclear forces and about $400 billion to modernize them.
That planned nuclear modernization would boost the total costs of nuclear forces over 30 years by roughly 50 percent over what they would be to only operate and sustain fielded forces, CBO estimates. During the peak years of modernization, annual costs of nuclear forces would be roughly double the current amount. That increase would occur at a time when total defense spending may be constrained by long-term fiscal pressures, and nuclear forces would have to compete with other defense priorities for funding.
In its first few months, the Trump Administration began a new Nuclear Posture Review to determine a nuclear policy and force structure “appropriately tailored to deter 21st century threats.” That review may recommend changing modernization plans and force sizes inherited from the Obama Administration to reflect the Trump Administration’s priorities for nuclear forces or to shift resources to address other defense priorities in the face of long-term budgetary pressures.
To assist policymakers, CBO examined nine options that could be pursued to lower or delay the costs of planned modernization. Some options would keep forces at or near the limit of 1,550 deployed warheads permitted under the New START treaty; others would reduce forces to around 1,000 deployed warheads. Those cuts to the forces would, to varying degrees, reduce the capability of future nuclear forces relative to those of forces as planned in 2017, although all components that would be retained in the options would be modernized.
What Are the 30-Year Costs of Planned Nuclear Forces?
CBO projects that the 2017 plan for nuclear forces would cost a total of $1.2 trillion from 2017 to 2046. Of that amount:
- $772 billion would be allocated for the operation, sustainment, and modernization of strategic nuclear delivery systems and weapons—the long-range aircraft, missiles, and submarines that launch nuclear weapons; the nuclear weapons they carry; and the nuclear reactors that power the submarines (see table below).
- $25 billion would be allocated for the operation, sustainment, and modernization of tactical nuclear delivery systems—the aircraft capable of delivering nuclear weapons over shorter ranges—and the weapons they carry.
- $445 billion would be allocated for the complex of laboratories and production facilities that support nuclear weapons activities and the command, control, communications, and early-warning systems that enable the safe and secure operation of nuclear forces.
Any changes that the Trump Administration or the Congress makes to modernization plans or the size of nuclear forces could affect those costs. In the Department of Defense’s (DoD’s) parlance, sustainment means providing a series of incremental upgrades over time to a system, often by developing and inserting components that are easier to maintain or that add capability, whereas modernization means performing a complete refurbishment of an entire system or developing and producing new versions of a system.
To estimate costs, CBO projected agencies’ budgets of the costs to operate and sustain the nuclear forces that exist today and combined those projections with CBO’s independent estimates of the costs of major new nuclear systems. Those calculations also include CBO’s estimates of cost growth beyond projected budgeted amounts for other modernization programs and for operation and sustainment of current and next-generation nuclear forces. (Those estimates are based on historical experience; see Appendix A for more details on CBO’s approach to estimating costs.)
Many of today’s nuclear weapon systems were designed and built decades ago and are nearing the end of their service life. According to DoD, if the United States wishes to continue to field nuclear forces, it will need to refurbish or replace essentially all elements of the forces that it decides to retain. Overall, CBO estimates that planned modernization would cost $399 billion through 2046 and include these programs:
- A new ballistic missile submarine (SSBN), designated the Columbia class;
- A new silo-based intercontinental ballistic missile (ICBM) and refurbished silos and other supporting infrastructure for ICBMs through the Ground-Based Strategic Deterrent (GBSD) program;
- A new long-range stealthy bomber, designated the B-21;
- Refurbishment of the current-generation D5 submarine-launched ballistic missile (SLBM);
- A new SLBM to eventually replace the D5;
- A new air-launched nuclear cruise missile, the Long- Range Standoff (LRSO) weapon;
- A life-extension program (LEP) for the B61 nuclear bomb that would combine several different varieties of that bomb into a single type, the B61-12;
- A LEP for the B61-12 bomb when it reaches the end of its service life, referred to as the Next B61;
- LEPs for the SSBN-related W76 and W88 warheads;
- A LEP to refurbish the W80 warhead that would be used on the LRSO; and
- A series of LEPs that would produce three interoperable warheads (called IW-1 through IW-3), each of which would be compatible with both ICBMs and SLBMs.
The rising costs of modernization would drive the total annual costs of nuclear forces, including operation and sustainment, from $29 billion in 2017 to about $50 billion through the early 2030s, CBO estimates. As most modernization programs reach completion, costs would gradually fall to around $30 billion a year in the 2040s (see figure below).
What Are Some Options for Managing the Costs of Nuclear Forces?
Some policymakers have raised concerns about the rising costs of nuclear forces. CBO analyzed three broad approaches that the United States could take to manage those costs. The first approach offers one option that would delay some modernization programs but would eventually achieve the currently planned force structure. The second approach offers five options that would reduce force structure but keep the number of warheads at New START limits. The third offers three options that would reduce the size of forces and the number of warheads below New START limits. The latter two approaches would affect both the costs and capabilities of modernized forces.
If those options were implemented for the next generation of systems, savings through 2046 would range from $27 billion to $139 billion, or from 2 percent to 11 percent of the total 30-year costs of nuclear forces (see figure below). Although the options would make substantial, or even complete, cuts to specific strategic and tactical nuclear weapons and delivery systems, the percentage reduction in overall costs would be limited because no single segment of the strategic nuclear triad (SSBNs, ICBMs, and bombers) would represent more than 25 percent of the total costs. Moreover, there are substantial fixed costs involved in maintaining the capability to safely and reliably field nuclear weapons. CBO assumed that the nuclear command-and- control systems and the complex of nuclear laboratories, which together constitute about 36 percent of the total costs of nuclear forces, would not change under any of the options.
One Option That Would Delay Modernization but Still Achieve the Planned Force Structure
CBO analyzed an option that would delay development of three programs: the new ICBM portion of the GBSD program, the B-21 bomber, and the interoperable warheads. Delaying those programs would reduce the peak costs of modernization by pushing some costs into later years without changing the final modernized force structure. Under Option 1, average annual costs would be $5 billion lower than costs of the 2017 plan over the first 20 years. Over the following 10 years, however, as the delayed programs ramped up activity, average annual costs would rise to $4 billion higher than the costs of the 2017 plan. Some costs would be pushed beyond the 30-year time frame considered in this report, so annual costs under Option 1 would exceed annual costs of the 2017 plan for some time after 2046.
Five Options That Would Reduce Delivery Systems but Maintain the Number of Warheads at New START Limits
CBO analyzed five alternative force structures that would cancel or scale back selected modernization programs but retain the number of deployed warheads at (or near) the limit of 1,550 set by New START. Those options would reduce costs relative to those of the 2017 plan, but they would also decrease capability and could have implications for strategic stability, escalation management, and the survivability of strategic forces. To illustrate the operational impact of the options, CBO assessed the capability of alternative force structures, relative to the capability of nuclear forces under the 2017 plan, in three types of operational scenarios: crisis management (that is, raising the alert status of nuclear forces or operating them in a way intended to forestall escalation in a crisis situation), limited nuclear strikes, and large-scale nuclear exchanges.
Options 2, 3, and 4 would each retain the nuclear triad. Two of those would forgo one of the bomber weapons (the LRSO in Option 2 and the B61-12 bomb in Option 3); Option 4 would field fewer SSBNs and ICBMs. If those options were implemented for the next generation of systems, they would save between $27 billion and $30 billion over 30 years relative to the costs of the 2017 plan, CBO estimates. All of those options would result in a capability similar to or somewhat less than that of planned forces for crisis management and limited strike scenarios, and the option with fewer ICBMs would have somewhat less capability than that of planned forces under a scenario that involved a large-scale exchange of nuclear weapons.
CBO also considered two options that would eliminate one of the segments of the triad: Option 5 would remove the nuclear mission from strategic bombers and tactical aircraft (leaving a dyad of SSBNs and ICBMs), and Option 6 would eliminate ICBMs (leaving a dyad of SSBNs and bombers). CBO estimates that—if it was implemented for the next generation of systems—Option 5 would save $71 billion over 30 years relative to the costs of the 2017 plan, although a substantial fraction of those savings would depend on DoD’s choosing to purchase 20 fewer B-21 aircraft because the nuclear mission had ceased. Option 6 would save $120 billion—or 10 percent of projected costs—over 30 years, CBO estimates.
Both dyad options would reduce capability substantially. Option 5, with no nuclear bombers, would provide significantly less capability in crisis management and in a limited nuclear strike, CBO estimates. Some analysts argue that such a change in capability would have serious implications for U.S. strategy and extended deterrence; other analysts contend that having less capability for limited strikes is a benefit because the risk of escalation to a large-scale nuclear exchange makes even limited nuclear strikes dangerous. Option 6, with no ICBMs, would lessen U.S. capability in large-scale nuclear exchanges by significantly reducing the number of targets an adversary would need to destroy to neutralize U.S. nuclear forces. According to some analysts, that possibility could significantly undermine deterrence; other analysts contend that deterrence would remain strong as long as enough warheads on SSBNs would survive any adversary’s first nuclear strike to guarantee a substantial retaliatory strike.
Three Options That Would Reduce the Number of Delivery Systems and Warheads Below New START Limits
CBO analyzed three options that would reduce the number of warheads and delivery systems below New START limits. Under those options, deployed warheads would be limited to 1,000 and delivery systems would be reduced in proportion to similar CBO options that would retain 1,550 warheads. Option 7 would maintain the nuclear triad, Option 8 would field a dyad with no strategic bombers, and Option 9 would field a dyad with no ICBMs.
If they were implemented for the next generation of systems, the 1,000-warhead options would save between $66 billion and $139 billion over 30 years relative to the costs of the 2017 plan, CBO estimates. Those savings are about $20 billion to $40 billion larger than the savings under Options 4, 5, and 6 (which would maintain weapons and delivery systems at New START levels). Among all the options CBO examined, Option 9 would save the most: $139 billion (or 11 percent). In general, the capability under each option that is limited to 1,000 warheads would be similar to that under the 1,550-warhead option it resembles, except that the capability for large-scale nuclear exchanges would be diminished for Options 7 and 8 because of their smaller ICBM forces.