It is in vogue to say that the role of nuclear weapons and realities of deterrence have fundamentally changed, a belief that is to some extent true. The United States no longer faces a superpower rival, instead encountering numerous diffuse threats from non-state organizations, hostile regimes, and rising powers. Indeed, the most urgent nuclear threat the United States currently faces is the transfer of sensitive nuclear material or an intact bomb to an anti-American terrorist organization, not an attack by a nuclear peer. 2 At present, the United States also enjoys vast superiority in conventional military capabilities that are likely to effectively deter and if necessary defeat any plausible military challenge that affects important U.S. interests without escalation to the nuclear level. For these reasons and others, the Obama administration determined that pursuing the long-term goal of a world without nuclear weapons is in the U.S. interest. 3
However, that is not to say nuclear weapons no longer have a role. To the contrary, they continue to make a vital contribution to U.S. national security by holding at risk what potential adversaries value most. As the 2010 Nuclear Posture Review (NPR) Report makes clear: “The fundamental role of U.S. nuclear weapons, which will continue as long as nuclear weapons exist, is to deter nuclear attack on the United States, our allies, and partners.” 4 And the deterrent effect of nuclear weapons extends beyond nuclear attack. Any leader contemplating the use of military force (including chemical and biological weapons) to challenge a vital U.S. interest must consider the possibility that the conflict will escalate to nuclear use, at which point the country’s military forces, economic infrastructure, and leadership would all be threatened. Without an ability to control escalation, it is difficult for an adversary to initiate a conflict that threatens core U.S. interests. 5
A strong U.S. nuclear deterrent also helps assure allies that, in forgoing their own nuclear capability, they can rely on the United States to guarantee their national survival. By including European and Asian allies under its nuclear umbrella, the United States advances two goals simultaneously: first, protecting countries who share U.S. interests and values; and second, dissuading additional countries from acquiring nuclear weapons. Nuclear guarantees are unique to the United States and make its nuclear deterrent all the more important.
Perhaps most of all, the U.S. nuclear arsenal serves as the ultimate national insurance policy. While there are many reasons to be optimistic about American strength for years to come, the unipolar moment will not last forever. Change often comes abruptly and unexpectedly, and even the most seasoned experts have proven surprisingly inaccurate when predicting the evolution of geopolitical events. 6 By 2050, the United States may face a dramatically different security environment featuring a resurgent Russia or a nuclear-capable Iran. If China chooses to channel its staggering economic growth into improved military capability, the United States might lose conventional superiority in the western Pacific, which may lead China to more assertively pursue its economic and territorial interests. 7 While none of these scenarios is a foregone conclusion, the fact remains that a more challenging security environment—whether in the form of a highly proliferated world or a return to bipolarity—is a realistic possibility that requires the retention of a credible nuclear deterrent.
Sea-Based Nuclear-Force Factor
The nuclear triad provides a unique combination of capabilities, giving the United States confidence that technological or geopolitical developments will not affect its ability to hold at risk what an adversary values most. Nuclear-capable bombers offer options for discrete attacks using lower-yield bombs with earth-penetrating capability. They can be forward-deployed or put on alert to signal resolve. ICBMs can be launched very quickly, are accurate, and are deployed in dispersed, hardened silos. SLBMs at sea are impervious to an enemy first strike and can easily be moved and retargeted.
While each leg makes an essential contribution, SLBMs are the most important. Against nuclear peers, such as Russia and someday possibly China, SLBMs are the most survivable and therefore stabilizing. Even after absorbing a massive first strike that could conceivably disable ICBMs and strategic bombers, the United States retains the ability to retaliate within minutes with hundreds of highly accurate, positively controlled warheads from nuclear-powered ballistic-missile submarines (SSBNs) on patrol. This has a stabilizing effect on both sides. For an opponent, preemption is not an attractive option. At the same time, the United States, knowing its forces are survivable, can remain calm in a crisis and avoid potentially destabilizing actions such as raising alert levels or preparing to launch on warning. 8
Against smaller nuclear powers such as North Korea and someday possibly Iran, SLBMs are also critical. In a conflict with these adversaries, the United States would be less concerned with a disarming first strike. Instead, it seeks the ability to strike discrete and potentially fleeting targets such as leadership or nuclear, chemical, and biological weapons capabilities. Nuclear bombers offer more flexibility for discriminate strike options, but can take a long time to reach targets and are vulnerable to air defenses. ICBMs offer a prompt option, but would have to fly over Russia on their way to most other targets. SSBNs on deterrent patrol in both the Atlantic and the Pacific give the United States an option for a quick nuclear strike without these concerns. 9
At the height of the Cold War, the U.S. nuclear force totaled more than 2,200 deployed delivery systems and approximately 13,000 deployed warheads. 10 In the two decades since the Cold War ended, the United States has, mostly in reciprocal agreements with Russia, substantially reduced those numbers. Some systems, such as the Peacekeeper missile, have been retired, while others, such as the B-1 bomber, have been shifted to exclusively conventional roles. Still, the United States retains a triad of 450 Minuteman III ICBMs, 19 B-2 bombers, 94 B-52 bombers, and 14 Ohio -class SSBNs that each carry 24 Trident II (D-5) missiles. 11
The next planned reduction will occur under the terms of New START, which entered into force on 5 February 2011. New START requires the United States and Russia to trim their respective strategic nuclear arsenals to 1,550 deployed, treaty-accountable warheads (reentry vehicles and bombers), 800 total launchers (missile tubes and bombers), and 700 deployed launchers (missile tubes containing missiles and bombers) by 2018. The treaty lasts through 2021 and has an option for a five-year extension.
While significant for its continuation of a verification arrangement that increases predictability and trust between the two sides, the reductions required by New START are quite modest. To comply, the United States will have to eliminate 80 launchers and remove approximately 600 deployed warheads. It is expected that the Obama administration will meet these requirements by cutting back the number of deployed ICBMs from 450 to 400, reducing the number of active launchers on each SSBN from 24 to 20, and retiring a few B-52 bombers. 12 Under this new arrangement, SLBMs would carry about 70 percent of deployed nuclear warheads, up from about 50 percent.
Replacing Systems in an Era of Austerity
The more difficult political and strategic decisions will come as the United States balances investment in the modernization of its nuclear-weapons complex, life-extension programs for its warheads, and replacements for its strategic delivery systems against other national-security priorities. The Obama administration committed to request $85 billion over ten years to modernize the U.S. nuclear-weapons complex and more than $100 billion over 20 years to replace nuclear delivery systems. However, maintaining those levels of support in Fiscal Year 2012, let alone the out years, will be a Herculean task. The 2011 Budget Control Act includes a sequestration mechanism that would require $54.7 billion in defense cuts each year from 2013 to 2027. Whether or not those cuts are enacted, it is clear that tremendous pressure on federal budgets, and defense budgets in particular, will continue, making difficult choices inevitable.
The defense budget crunch could not come at a worse time for strategic systems. The Air Force is in the midst of a refurbishment program for the Minuteman force, which will extend its service life through 2030, and has started a study that will recommend a specific way ahead for the ICBM follow-on. The B-52 bomber, which has been in operation since the 1950s, will need to be retired around 2035. 13 For the Navy, Ohio -class SSBNs will commence decommissioning in 2027, requiring a next-generation ballistic-missile submarine, or SSBN(X). A study of the replacement is already under way, and procurement of the first replacement is expected to begin in the next five years. Maintaining a strong coalition in support of these modernization and replacement efforts will not be easy. For many defense hawks, more usable conventional military capabilities are more important than nuclear platforms. At the same time, those committed to abolition argue that nuclear modernization is an extravagance that could undermine U.S. nonproliferation credibility internationally.
The Navy in particular will continue to face budget pressures. Each SSBN(X) is expected to cost from $5–6 billion, which the most recent shipbuilding plan recognizes will put enormous strain on the overall Navy shipbuilding budget. 14 The timeline for the introduction of the first new submarine already has been pushed back from 2029 to 2031 in order to realize near-term cost savings, and the Pentagon is looking for ways to further decrease the per-unit cost of the SSBN(X). 15 The Navy also must consider a replacement for the D-5 missile, which will initially be deployed on current Ohio -class submarines and then the SSBN(X). Under New START, the United States plans to deploy a sea-based nuclear force consisting of 12 SSBNs with 20 active tubes, each loaded with Trident missiles carrying between one and eight reentry systems. However, because of the delay in the SSBN(X) purchase, the Navy will only have 10 vessels at sea throughout the 2030s, dipping below the current requirement of 12. 16
A number of cost-saving options have been proposed—reducing the number of SSBNs to 10 or even 8, reducing the number of tubes on the SSBN(X), operating submarines in a single ocean, designing a common missile for the Navy and the Air Force, and even adding SLBM tubes to attack submarines—each of which would have budgetary and strategic consequences. Some options, such as limiting SSBN patrols to a single ocean, are likely to be quickly dismissed. Closing the base at Kings Bay, Georgia, or Bangor, Washington, would bring additional short-term costs associated with moving personnel and equipment and refitting one of the bases to handle additional submarines. More important, limiting the patrol area to either the Atlantic or the Pacific would limit flexibility in covering targets, and increase the risk that SSBNs could be detected.
Other options, such as reducing the number of SSBNs, are likely to be considered more seriously; the high per-unit cost of each additional SSBN makes them an attractive target. The Navy argues that it requires a minimum of 12 SSBNs to meet the requirement to have 5 boats on deterrent patrol at all times. 17 Therefore, reducing the number of boats likely would require the President to reduce or otherwise adjust U.S. targeting requirements. But even with updated targeting plans, the Navy might compensate for having fewer boats by designing in more tubes in the SSBN(X) and/or arming each SLBM with more warheads. Trident missiles can carry up to 8 reentry vehicles, and the average is likely to be just over 4 once New START is fully implemented. Loading additional warheads would decrease the range of individual missiles and limit their usefulness for discrete strikes. As the Navy considers reducing the number of SSBNs and other cost-saving measures, it must ensure that it doesn’t sacrifice long-term strategic requirements for short-term budgetary goals.
The Budget/Strategy Balancing Act
While the upfront costs of replacing the sea-based nuclear deterrent are substantial, the operating costs of SSBNs are relatively modest. 18 Over the next few decades, SSBNs will make a vital contribution to U.S. national security, while costing only a fraction of the overall defense budget. Nonetheless, financial pressures and tradeoffs are real, and the Navy will be forced to make difficult decisions. The Obama administration—and potentially a new Republican administration—can help by continuing to review nuclear requirements and clearly outlining the role, missions, and number of nuclear weapons that are necessary to meet deterrence goals. New guidance, which will likely find ways to relax targeting requirements, will allow the Navy to design replacement boats and missiles that allow it to maintain an effective sea-based deterrent in the most cost-efficient way possible.
It is important to remember that decisions made in the next few years will have effects that last for decades. The next generation of SSBNs and SLBMs will come online in the 2030s and be expected to operate through 2080. The United States must plan for the range of security environments that are possible and ensure that it designs a flexible force posture that can adapt to each. By 2050, the United States could face a highly proliferated world, significant progress toward a world without nuclear weapons, or something in between. But at this point, there is little reason to think that the world’s nuclear powers will give up their weapons within the service life of a follow-on SSBN, and it would be irresponsible to plan as if they will.
The United States must maintain a strong sea-based nuclear force that can effectively deter nuclear peers and smaller nuclear powers alike, and it must do so in a way that controls cost as much as possible. The optimal SSBN force for the 21st century should be determined by a combination of capabilities, strategic requirements, and cost. Getting the balance right is crucial.
1. Barack Obama, “Remarks of President Barack Obama,” (speech given at Hradc?any Square, Prague, Czech Republic, 5 April 2009), www.armscontrol.org/node/3626  .
2. Nuclear Posture Review Report (Washington, DC: Department of Defense, April 2010), iv–v, www.defense.gov/npr/docs/2010%20nuclear%20posture%20review%20report.pdf  .
3. Ibid., 45–49.
4. Ibid., 15.
5. Deterrence Operations Joint Operating Concept (Washington, DC: Department of Defense, December 2006), 39–40.
6. Daniel Kahneman, Thinking, Fast and Slow (New York: Farrar, Straus, and Giroux, 2011), 218–220.
7. See for example Arvind Subramanian, “The Inevitable Superpower,” Foreign Affairs , September/October 2011, www.foreignaffairs.com/articles/68205/arvind-subramanian/the-inevitable-...  and James Kurth, “Confronting a Powerful China with Western Characteristics,” Orbis 56:1 (2011): 39–59, http://dx.doi.org/10.1016/j.orbis.2011.10.003  .
8. Christopher A. Ford, “Dilemmas of Nuclear Force ‘De-Alerting’,” Hudson Institute, 7 October 2008, 3–4, www.hudson.org/files/documents/De-Alerting%20FINAL2%20%282%29.pdf  .
9. Thomas Scheber, “Whither the Triad: Considerations for a Triad, Dyad or Monad,” in Taylor Bolz (ed.), In the Eyes of the Experts (Washington, DC: United States Institute for Peace, 2009), 71.
10. Amy Woolf, “U.S. Strategic Nuclear Forces: Background, Developments, and Issues,” Congressional Research Service, 22 February 2012, 2–3.
11. Ibid., summary.
12. Ibid., 8.
13. Department of Defense, “November 2010 Update to the National Defense Authorization Act of FY2010, New START Treaty Framework and Nuclear Force Structure Plans,” 17 November 2010, 11, www.lasg.org/CMRR/Sect1251_update_17Nov2010.pdf  .
14. Deputy Chief of Naval Operations, Annual Report to Congress on Long-Range Plan for Construction of Naval Vessels for FY2013 (Washington, DC: Office of the Chief of Naval Operations, April 2012), 14-18.
15. Tom Z. Collina, “Pentagon Budget Delays New Nuclear Subs,” Arms Control Association, March 2012, www.armscontrol.org/act/2012_03/Pentagon_Budget_Delays_New_Nuclear_Subs  .
16. Elaine M. Grossman, “U.S. Navy to Grapple with Dip in Deployed Subs for More Than a Decade,” Global Security Newswire , 30 March 2012, www.nti.org/gsn/article/us-navy-grapple-dip-deployed-subs-more-decade/  .
17. Tom Z. Collina, “Pentagon Considers New Nuclear Cuts,” Arms Control Association, December 2011,
18. ADM Richard W. Mies, “The SSBN in National Security,” Undersea Warfare , 2:1 (Fall 1999): www.navy.mil/navydata/cno/n87/usw/issue_5/ntlsecurity.html  .
What Will Follow the Ohio Class?
By Captain Dave Bishop, U.S. Navy
The year 2011 was a watershed for the Ohio Replacement Program Office. The Milestone A Acquisition Defense Memorandum, issued 10 January 2011, officially authorized the Ohio replacement SSBN to enter the technology development phase. Over the past year, the Ohio Replacement Program worked to solidify requirements, a key step in finalizing the service-approved Capability Development Document. The program also has progressed in the development of common missile compartment (CMC) quad-pack ship specifications and the definition of propulsion-plant and hull/mechanical/electrical (HM&E) systems, and completed significant prototyping work.
The current configuration of the Ohio replacement is an SSBN with 16 87-inch-diameter missile tubes, a 43-foot-diameter hull, fairwater planes, electric-drive propulsion, X-stern, accommodations for 155 personnel, and a common submarine radio room tailored to the SSBN mission. The vessel will utilize the existing Trident II (D-5) life-extended strategic-weapon system (SWS).
Through small-scale model testing, the program postulated various hull configurations, including bow planes and stern configurations that included H-stern, cruciform with vertical stabilizers, and hybrid X-stern before finally deciding on the X-stern. A CMC design will be shared by both the United States and the United Kingdom as it moves forward with its successor program that will replace the current British Vanguard -class SSBNs. Recognizing missile-compartment construction is a major cost-contributor to an SSBN construction project, the Ohio Replacement Program is developing a missile-compartment build strategy to leverage modular-construction techniques that will help maximize cost savings as compared to the Ohio class. The previous “stick-built” method of construction used in all previous SSBN classes involved fabricating the hull first, then cutting the hull to insert the missile tubes. After installation in the hull, the shipbuilders would outfit the missile tube. This is a time-consuming, labor-intensive process with a majority of the outfitting being done less optimally within the hull.
During the past year, the Navy successfully completed prototyping the Integrated Tube and Hull (ITH) build strategy for the missile compartment. General Dynamics Electric Boat Division competitively awarded subcontracts to four companies, two in the United States and two in the United Kingdom, to produce prototype missile tubes. This process allowed the Navy to verify that the industrial base can produce large missile tubes to tight tolerances, and it creates the opportunity to compete the production work for the missile tubes that will ensure the best value to the Navy.
Employing this build strategy, missile-tube vendors will supply tubes with the upper portion of the pressure hull, known as the crown, to the shipbuilder. The shipbuilder then outfits the missile tubes off-hull and welds the four crown assemblies together using the E-fixture that maintains tube alignment while welding. The four tubes then are welded into a section of the pressure hull to form a “quad pack” that is joined with other such foursomes to create the missile compartment. The successful completion of the ITH build-strategy prototype in 2011 proved the effectiveness of this modular assembly method.
In January 2012, Secretary of Defense Leon Panetta announced a two-year program delay with lead-ship construction starting in Fiscal Year 2021 instead of 2019. This two-year delay will slow the rest of ship-design development consistent with reduced near-term funding while allowing more time for risk-reduction and cost-reduction efforts to proceed. The program will maintain key elements of the baseline design schedule to support the CMC for the U.K. successor program including the SWS development and propulsion-plant design progress to support the later construction start. These elements include ship specifications, key HM&E system definition and diagrams, design-for-affordability efforts, auxiliary machinery room I and II, integrated product-design environment, and select CMC support systems and arrangements.