The Office of the Secretary of  Defense and the Joint Staff led the effort in consultation with the  Departments of State and Energy. In support of this objective, the United States  signed a new Strategic Arms Reduction Treaty with Russia—known as  New START—on April 8, 2010, which entered into force on February 5,  2011. According to DOD’s April 2014 report on its plan to implement  New START, DOD plans to maintain 400 deployed intercontinental  ballistic missiles; 240 deployed submarine-launched ballistic missiles; and  60 deployed heavy bombers. DOD and  military service officials told us these numbers reflect DOD’s current  planned strategic force structure for implementing New START. Figure 1  shows DOD’s planned deployed strategic force structure for implementing  New START, including the number of delivery vehicles for each leg of the  triad. DOD Assessed the Need for Each Leg of the Strategic Triad in the 2010 NPR and Considered Other Reductions to Nuclear Forces in Subsequent Reviews

DOD assessed the need for each leg of the strategic triad in support of  the 2010 NPR and considered other reductions to nuclear forces in  subsequent reviews. The department identified advantages of each leg of  the triad and concluded that retaining all three would help maintain  strategic deterrence and stability. The 2010 NPR report states that the  administration considered various options for U.S. nuclear force structure,  including options in which the United States would eliminate one leg of  the triad. DOD officials also told us that the department had assessed  nuclear force reductions as part of subsequent reviews, including during  the development of the President’s nuclear employment guidance, the  2013 Strategic Choices Management Review, and the development of  DOD’s plan to implement New START. These advantages—including the  survivability of the sea-based leg; the intercontinental ballistic missiles’  contribution to stability; and the ability of the nuclear-capable bombers to  visibly forward deploy—are further described in Navy and Air Force  acquisition documents completed both before and after the 2010 NPR,  from 2008 through 2014. DOD officials were unable to provide us  documentation of the NPR’s analysis of the strategic force structure  options that were considered; officials from the Office of the Secretary of  Defense, Joint Staff, and Strategic Command told us that much of the  NPR analysis on the consideration of different strategic force structure  options was discussed in senior-level meetings and was not documented. In addition to the discussions and analysis of options for alternative  strategic force structures that occurred during the development of the  2010 NPR, Strategic Command, Air Force, and Navy officials told us that  they had also analyzed alternative strategic force structures in advance of  the NPR discussions. Agency Comments

We provided a draft of the classified version of this report to DOD for  review and comment. In response to that draft report, DOD provided  technical comments that we have incorporated as appropriate.
Why GAO Did This Study

Since the 1960s, the United States has deployed nuclear weapons on three types of strategic delivery vehicles collectively known as the strategic triad. The triad comprises the sea-based leg (submarine-launched ballistic missiles), ground-based leg (intercontinental ballistic missiles), and airborne leg (nuclear-capable heavy bombers). As a result of arms control agreements and strategic policies, the number of U.S. nuclear weapons and strategic delivery vehicles has been reduced substantially; however, the strategic triad has remained intact. DOD and the Department of Energy are planning to invest significant resources to recapitalize and modernize the strategic triad in the coming decades. The departments projected in 2015 that the costs of maintaining U.S. nuclear forces for fiscal years 2016 through 2025 would total $319.8 billion, and DOD expects recapitalization and modernization efforts to extend into the 2030s.
GAO was asked to review DOD's analysis of the decision to retain all three legs of the strategic triad. This report describes the processes DOD used in supporting that decision. GAO reviewed documentation and interviewed officials from DOD and the military services on the key reviews DOD carried out from 2009 to 2014— including the 2010 Nuclear Posture Review—in analyzing its strategic force structure.

What GAO Found

The Department of Defense (DOD) assessed the need for each leg of the strategic triad in support of the 2010 Nuclear Posture Review and considered other reductions to nuclear forces in subsequent reviews. The department identified advantages of each leg of the triad and concluded that retaining all three would help maintain strategic deterrence and stability. The advantages DOD identified include the survivability of the sea-based leg, the intercontinental ballistic missiles' contribution to stability, and the ability of the nuclear-capable bombers to visibly forward deploy. The 2010 Nuclear Posture Review Report states—and DOD officials also told GAO—that the administration has considered various options for the U.S. nuclear force structure, including options in which DOD would eliminate one leg of the triad. For example, Strategic Command, Air Force, and Navy officials told GAO that they had analyzed alternative strategic force structures in preparation for the 2010 Nuclear Posture Review. DOD officials also told GAO that the department had assessed nuclear force reductions as part of reviews conducted after the Nuclear Posture Review, including during the development of the President's 2013 nuclear employment guidance, the 2013 Strategic Choices Management Review, and DOD's 2014 plan to implement the New Strategic Arms Reduction Treaty (New START) with Russia. The figure shows DOD's current planned strategic force structure for implementing New START, including the number of delivery vehicles that would be retained for each leg of the triad.
This is a public version of a classified report GAO issued in May 2016. It excludes classified information on warhead levels, the specific advantages of each leg of the triad, and some of the analyses of alternatives that were considered.

What GAO Recommends

GAO is not making any recommendations in this report. DOD provided technical comments, which were incorporated as appropriate.