The version of the Fiscal Year (FY) 2024 National Defense Authorization Act (NDAA) the House Armed Services Committee (HASC)REF passed on June 22, 2023, by a vote of 58–1REF will strengthen U.S. strategic defenses.REF The NDAA is the legislation that identifies the priorities and major programs of the Department of Defense (DOD); sets recommended funding levels; and establishes the policies under which DOD money will be spent. The draft bill, which must now go to the full House for a vote, pauses the retirement of the B83 nuclear gravity bomb; sustains the nuclear-capable Sea-Launched Cruise Missile (SLCM-N) and Long-Range Standoff (LRSO) nuclear cruise missile programs; and supports an array of enhancements to missile defense capabilities. While this bodes well for the FY 2024 NDAA, more can and should be done to strengthen America’s deterrent.

In particular, the FY 2024 NDAA should expand Guam’s missile defenses in the immediate term using AEGIS afloat capabilities; expand U.S. missile defenses in North America; and lay the groundwork for a strengthened and more diversified nuclear deterrent by: (1) exploring the feasibility of fielding a road-mobile Sentinel Intercontinental Ballistic Missile (ICBM); (2) considering a long-range nuclear-tipped anti-ship missile; and (3) creating a foundation to upload multiple independently targetable reentry vehicles (MIRVs) to the ballistic missile force.

Why an Effective Deterrent Is So Important

As Russia’s invasion of Ukraine surpasses its 500th day, Moscow increasingly rattles its nuclear saber. In June, Russian President Vladimir Putin announced that Russia will deploy nuclear-armed missiles to Belarus by early July, and told Russian military bloggers that Western support for Ukraine makes nuclear war a “distinct possibility.”REF

According to the DOD’s 2022 China Military Power Report, China’s nuclear stockpile will achieve numeric parity with the United States by the middle of the next decade—with no indications that it will stop increasing at that time.REF Indeed, with the U.S. and Russian withdrawal from the Intermediate-Range Nuclear Forces (INF) treaty and the Russian suspension of the New Strategic Arms Reduction Treaty (New START) nuclear arms control treaty—both of which limited the growth and composition of the American and Russian (but not Chinese) nuclear arsenals for many years—there are no legal limits to the size and diversity of the Russian and Chinese nuclear arsenals.

To deter nuclear coercion, while at the same time defending American and allied homelands from these nuclear powers, it is imperative that the United States maintain a robust and credible nuclear deterrent coupled with effective missile defenses.REF

What the HASC’s Version of NDAA Gets Right

There is a lot to like about the HASC version of the FY 2024 NDAA, the first produced by the new Republican majority in the House.

The B83. First, the B83, the most powerful nuclear bomb in the American inventory, will not be retired immediately. President Biden’s 2022 Nuclear Posture Review (NPR) “retired” the B83, citing that “existing capabilities” would be used to hold at risk hard and deeply buried targets.REF Examples of such targets include rogue regime underground command bunkers or uranium enrichment facilities.

However, the NPR did not identify what those “existing capabilities” would be. The HASC version of the NDAA rightly prohibits the retirement of more than 25 percent of the B83s until the DOD submits options to Congress about how it will hold such targets at risk.REF

NC3 Architecture. The HASC version of the NDAA strengthens America’s nuclear command, control, and communications (NC3) architecture by establishing an NC3 Major Force Program, a formal designation that allocates the resources and authorities required for a program to achieve DOD objectives and plans. It will also likely establish a new cybersecurity and risk group within the DOD to further protect NC3 and the broader, nuclear-related information technology enterprise.

The Sentinel Missile Program. The 2024 NDAA also requires the DOD to provide an integrated master schedule for the Sentinel missile program, which will replace the Minuteman III ICBM. Such an integrated master schedule should help prevent programmatic delays as Sentinel is fielded during the next decade. The Government Accountability Office highlighted Sentinel delays as a key concern in its June annual Weapon Systems Assessment to Congress.REF

Nuclear Detection and Modernization Efforts. Importantly, the HASC version of the NDAA requires that the DOD report any detected nuclear cooperation between China and Russia to Congress. It also directs ongoing nuclear modernization efforts, to include the building and fielding of the B-21 bomber; sustaining the LRSO nuclear-armed air-launched cruise missile program; and strengthening America’s ability to produce 80 plutonium pits by 2030 (the current target as part of the nuclear modernization program).REF

The SLCM-N. Perhaps most importantly, the HASC’s version of the NDAA establishes the SLCM-N as a program of record. A “program of record”—a designation for an acquisition program that is directed and funded to provide a new, improved, or continuing material, capability, or weapon in response to an approved need—gives the SLCM-N more permanence within DOD development and acquisition cycles. Further, it requires quarterly briefings from the Navy on the development of the SLCM-N and from the Department of Energy on the associated W80 warhead.

Missile Defense Strength. In addition, the NDAA strengthens missile defenses in important ways. It requires the Missile Defense Agency (MDA) to report to Congress on potential enhancements to missile defense sites in Poland and Romania, to include enhancing sensor systems to detect a greater array of missile threats, fielding a mixed fleet of missile interceptors in Europe, and physically hardening existing European facilities. The NDAA also requires the MDA to field a Glide Phase Interceptor that can defeat a hypersonic vehicle within the atmosphere by the end of the decade.

In short, these are all good, important steps that strengthen America’s deterrent and defensive capabilities.

What Congress Should Add to the NDAA

Although the above steps are needed, more is required given existing threats. As such, the FY 2024 NDAA should direct the DOD to take a number of relatively low-cost steps to shore up the U.S. deterrence posture. To wit:

Prepare to Place More Than One Warhead on Delivery Vehicles of the Ballistic Missile Force. Warhead limits imposed by the New START treaty caused the U.S. to reduce the number of weapons loaded on a single missile, shifting the U.S. missile inventory from MIRVs on a single missile to one weapon per missile. While the NDAA extends the DOD’s authority to re-add these additional nuclear warheads to the ballistic missile force, more should be done to include laying the programmatic groundwork to upload warheads to pre–New START levels. This is not to say that the U.S. should upload the warheads immediately—but America must be prepared to do so should the security situation rapidly deteriorate. Indeed, the ability to upload quickly may deter U.S. adversaries from taking provocative nuclear actions.

Examine the Utility of a Nuclear Anti-Ship Missile. The final NDAA should direct the DOD to examine the feasibility and utility of an integrated sensor and targeting package that would enable a long-range anti-ship missile to find, fix, and finish moving adversary naval assets with a nuclear warhead. An anti-ship variant of the LRSO or SLCM-N would give the President more graduated nuclear response options in the face of an adversary using nuclear weapons, thereby better deterring adversary limited nuclear strikes.

Such a capability is critical in scenarios in which the United States has bases spread across American and allied territories in a theater far from North America but is fighting a nuclear-armed adversary that does not. Should that adversary use a nuclear weapon on an American or allied target within theater, the United States would have no choice but to strike the adversary’s homeland if responding with a nuclear capability. Giving the United States the ability to strike an adversary surface vessel with a nuclear weapon would provide the President with a more graduated set of responses that are less likely to invite a nuclear response on the American homeland itself. An analysis of the desirability of such a capability is warranted.

Examine the Feasibility of Making the Sentinel ICBM Road-Mobile. A road-mobile ICBM would create significant targeting challenges for U.S. adversaries, thereby strengthening the U.S. deterrence posture by fielding an additional second-strike capability. Given the expansion of adversary intercontinental nuclear capabilities and the future potential that U.S. ballistic missile submarines may no longer be undetectable, an additional second-strike capability would go far to reduce risk.

Strengthen Missile Defenses on Guam in the Near Term. Congress should direct the Navy to expand missile defense capabilities on Guam in the immediate term—potentially using an AEGIS afloat system from one of the older ballistic missile defense cruisersREF—until a more permanent land-based, 360-degree missile defense system is in place.

Reinvigorate the Development and Fielding of the Next-Generation Interceptors. Given the deteriorating security environment, Congress should once again examine the feasibility and utility of increasing the number of interceptors at the West Coast sites and consider establishing an East Coast site. An increased missile defense capability that covers North America would defeat a limited salvo that an adversary may launch on North America and force the adversary to increase their salvo size in order to achieve similar effects.

By forcing adversaries to launch a sizable salvo on North America, even as part of a “limited” strike, they would have to consider the potential for and consequences of an American strategic response to such a large salvo (even if a substantial portion of that salvo was intercepted). Ultimately, an increased, credible North American missile defense capability could deter a limited strike on key targets in North America.

The Path Forward

There is much to like about the emerging NDAA. There is bipartisan consensus on the need to modernize the nuclear arsenal and field effective, theater-range nuclear-tipped cruise missiles. Forcing the DOD to identify a viable alternative to the B83 is wise, as are the efforts to modernize NC3. Congress understands that there is a danger that major reinvestments in the arsenal (particularly Sentinel) could fall behind, and it is taking the appropriate steps to stave off delays. The requirement for a Glide Phase Interceptor to be fielded before 2030 is most encouraging, as are the requirements to examine strengthening missile defenses in Europe and in U.S. naval platforms.

More should be done—particularly by adding additional nuclear warheads to the U.S. ballistic missile force and exploring a nuclear-tipped long-range anti-ship missile, as well as expanding ground-based missile defense capabilities—but the FY 2024 NDAA is on the right path with respect to nuclear and missile defense programs.

Robert Peters is Research Fellow for Nuclear Deterrence and Missile Defense in the Center for National Defense at The Heritage Foundation.