The spread of nuclear weapons is one of the most significant challenges to global security in the 21st century. Limiting the proliferation of nuclear weapons and materials may be the key to preventing a nuclear war or a catastrophic act of nuclear terrorism. Going Nuclear offers conceptual, historical, and analytical perspectives on current problems in controlling nuclear proliferation. It includes essays that examine why countries seek nuclear weapons as well as studies of the nuclear programs of India, Pakistan, and South Africa. The final section of the book offers recommendations for responding to the major contemporary proliferation challenges: keeping nuclear weapons and materials out of the hands of terrorists, ensuring that countries that renounce nuclear weapons never change their minds, and cracking down on networks that illicitly spread nuclear technologies.

Nearly all the chapters in this book have been previously published in the journal International Security. It contains a new preface and one chapter commissioned specifically for the volume, Matthew Bunn's "Nuclear Terrorism: A Strategy for Prevention."

CISAC contributors: Consulting Professor Chaim Braun, Co-Director Scott Sagan.

Other contributors, including former CISAC scholars: Samina Ahmed, Matthew Bunn, Christopher F. Chyba, Matthew Fuhrmann, Šumit Ganguly, S. Paul Kapur, Ariel E. Levite, Peter Liberman, Austin Long, Sean M. Lynn-Jones, Alexander H. Montgomery, Gaukhar Mukhatzhanova, William C. Potter, Whitney Raas, Etel Solingen.

This article presents a method developed to assess laser Directed Energy Weapon engagements. This method applies physics-based models, which have been validated by experiments. It is used to assess the capabilities of the Airborne Laser (ABL), a system for boost phase missile defense purposes, which is in development under supervision of the U.S. missile defense agency. Implications for international security are presented.

The article begins with a general introduction to laser Directed Energy Weapons (DEW). It is notable that several laser directed energy weapon prototypes have recently become operational for testing. One of them is the ABL, a megawatt-class laser installed into a cargo aircraft. It is concluded that only the ABL could have significant political impact on an international scale at the moment. Hence, the remainder of the article focuses on the assessment of that system. The laser intensity, the induced temperature increase of a target and the impact of this temperature increase on the mechanical properties of the target are calculated for different scenarios. It is shown that the defensive capability of the ABL against ballistic missiles is limited. Even a successful laser engagement that deflects a missile trajectory from its intended target can have negative impact for third parties, as missile warheads will most likely not be destroyed.

Executive Summary of Report

Nearly twenty years after the end of the Cold War, Russia and the United States continue to maintain hundreds of nuclear weapons capable of striking the other side, and to have at least some of these nuclear forces at Cold War levels of alert, that is, ready to fire within a few minutes of receiving an order to do so.

Even during the Cold War, alert levels were not static and moved up or down in step with changes in the strategic and tactical environments. While the operational readiness of some weapon systems has been reduced, there has been no major change in the readiness levels of most of the nuclear weapon systems in the post-Cold War era. This is in considerable part because Russia and the United States believe that despite fundamental changes in their overall relationship, vital interest requires maintaining a high level of nuclear deterrence.

The post-Cold War experience also demonstrates that alert levels can be reduced and measures can be taken to reduce the risk of accidents or unauthorized takeover of nuclear weapons. Further measures could be taken to reduce operational readiness of nuclear arsenals. U.S. and Russian experts alike stressed survivability as a key element in the acceptance of these measures because of its importance to maintaining deterrence.

Cold War legacy postures under which thousands of weapons are kept on high readiness can be altered through top-down policy initiatives, as was the case in the early 1990s with one class of nuclear weapons.

Technical issues related to the peculiar "ready" character of land-based ICBMs can be resolved by bringing designers into discussions on decreasing operational readiness of nuclear weapons. There was a sense that technical solutions to the problems of nuclear risk reduction are available and can be multilateralized. Information sharing can help implementation of these solutions.

Concerns over "re-alerting" races and vulnerability of "de-alerted" forces to conventional or nuclear strikes during "reversal" can be addressed through survivable forces, dialogue, and confidence building.

Other nuclear weapon states apparently have alert practices that differ from those of Russia and the United States. It was debated whether this state of affairs can be ascribed to an absence of nuclear war fighting capabilities or to a different assessment of the post-Cold War nuclear security environment. There was a sense that nuclear doctrines and alert practices of different nuclear weapon states cannot be analyzed in a vacuum and must be evaluated as parts of a larger political and security framework.

Non-nuclear weapon states' experts forcefully asserted the legitimate interest their states have in the issue and underlined the practical and constructive approach of the U.N. General Assembly resolution on reducing operational readiness of nuclear forces.

Non-nuclear weapon states say that lowering of the operational status of nuclear weapons would both reduce the risk of accidental or unintended nuclear war and provide a much-needed practical boost for disarmament and nonproliferation. Decreasing the operational readiness of nuclear weapons would be a highly desirable confidence-building measure between nuclear weapon states and non-nuclear weapon states. It would also be a welcome step in the lead-up to the 2010 Non-Proliferation Treaty (NPT) Review Conference.

The principal objection to decreasing operational readiness of nuclear weapons as commonly understood has been that it seeks to address a problem that does not exist. Even if it does exist in some instances, it can be addressed by technical and organizational means updated to cover current threats such as nuclear terrorism. Furthermore, the remedy itself could end up undermining nuclear deterrence and strategic or crisis stability.

The insight that emerged during the meeting was that the above objection flows from a narrow view of de-alerting as meaning measures that make it physically impossible to promptly launch an attack on order. Such a view also leads to a somewhat excessive focus on verification of technical measures, which ends up giving an easy argument to the opponents of de-alerting-that it is not verifiable and therefore should not be attempted.

There are no fundamental obstacles to many useful measures of decreasing operational readiness of nuclear weapons, provided the issue is not framed narrowly. De-alert has to be seen not only as a technical fix but also as a strategic step in deemphasizing the military role of nuclear weapons, in other words, moving to retaliatory strike postures and doctrines instead of legacy preemptive or "launch on warning" postures. The ongoing U.S. Nuclear Posture Review (NPR) offers an opportunity for such a perceptual shift.

If decreasing operational readiness of nuclear weapons is reframed in this manner, several concrete steps become possible:

As part of the START follow-on negotiations, Russia and the United States could examine how measures to reduce operational readiness can accompany the bilateral arms control process.

Both Russia and the United States could further strengthen controls against unauthorized action, takeover, and tampering; further increase the capability of warning systems to discriminate real from imagined attacks; and enhance the survivability of their forces and their command and control systems.

Arrangements related to data exchange and ensuring a capability to destroy a "rogue" missile in flight could be multilateralized, at least in terms of sharing data, to bring other declared nuclear weapon states into the process.

Multilateralization of institutions such as the Joint Data Exchange Center may also have collateral benefits in the area of space security.

The premise of maintaining nuclear deterrence between Russia and the United States should not be considered immutable. A dialogue on legacy nuclear postures and doctrines in the Russia-U.S. context may trigger a broader dialogue among relevant states on reducing the salience of nuclear weapons, thus facilitating progress on disarmament and nonproliferation.

Nuclear-armed adversaries India and Pakistan have fought three wars since their creation as sovereign states in 1947. They went to the brink of a fourth in 2001 following an attack on the Indian parliament, which the Indian government blamed on the Pakistan-backed Lashkar-e-Taiba and Jaish-e-Mohammed terrorist organizations. Despite some attempts at rapprochement in the intervening years, a new standoff between the two countries was precipitated when India accused Lashkar-e-Taiba of being behind the Mumbai attacks late last year.

The relentlessness of the confrontations between these two nations makes Inside Nuclear South Asia a must read for anyone wishing to gain a thorough understanding of the spread of nuclear weapons in South Asia and the potential consequences of nuclear proliferation on the subcontinent.

The book begins with an analysis of the factors that led to India's decision to cross the nuclear threshold in 1998, with Pakistan close behind: factors such as the broad political support for a nuclear weapons program within India's ruling Bharatiya Janata Party (BJP), the intense rivalry between the two countries, the normative and prestige factors that influenced their behaviors, and ultimately the perceived threat to their respective national security.

The second half of the book analyzes the consequences of nuclear proliferation on the subcontinent. These chapters show that the presence of nuclear weapons in South Asia has increased the frequency and propensity of low-level violence, further destabilizing the region. Additionally, nuclear weapons in India and Pakistan have led to serious political changes that also challenge the ability of the two states to produce stable nuclear détente. Thus, this book provides both new insights into the domestic politics behind specific nuclear policy choices in South Asia, a critique of narrow realist views of nuclear proliferation, and the dangers of nuclear proliferation in South Asia.