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851.
Damascus has severely impeded an investigation by the International Atomic Energy Agency (IAEA) into Syria's construction of a covert nuclear reactor, which was destroyed in a 2007 Israeli air strike. Pressing Damascus to cooperate with the inquiry is necessary to ascertain that there are no other undeclared activities in Syria, to determine the role of North Korea in the construction of the reactor, and to help prevent future clandestine efforts. With Damascus doing its best to avoid the investigation, securing Syrian cooperation will require adept diplomacy backed by the prospect of special inspections and, if necessary, a referral to the UN Security Council. The case of Syria's secret reactor highlights areas in which the IAEA needs buttressing, from the enhanced sharing of information, to reporting that is less political and more forthright. The case also illustrates the downside of politicizing IAEA investigations and supports the new director's apparent intent to return the agency to its core technical tasks.  相似文献   
852.
Export controls and international safeguards are central to ensuring international confidence in the peaceful uses of nuclear materials and technologies and to achieving adequate oversight on the transfer and use of nuclear materials, technology, and equipment required for the development of proliferation-sensitive parts of the nuclear fuel cycle. Although the independent strengths of export controls and international safeguards rely largely on universal adherence, there may be opportunities to exploit the shared strengths of these systems. This article provides background information on the separate evolution of export controls and international safeguards, considers how these two elements of the nonproliferation regime interact, and identifies some possible avenues that could, over time, lead to wholly integrated activities.  相似文献   
853.
For many years, non-nuclear weapons states have sought binding commitments from nuclear armed states that they would not be the victim of either the threat or use of nuclear weapons—so-called negative security assurances (NSAs). The nuclear weapon states have traditionally resisted granting such unconditional NSAs. Recent U.S. efforts to use nuclear deterrence against the acquisition and use by other states of chemical, biological and radiological weapons, however, have further exacerbated this divide. This article analyzes the historical development of NSAs and contrasts U.S. commitments not to use nuclear weapons with the empirical realities of current U.S. nuclear weapons employment doctrines. The authors conclude that NSAs are most likely to be issued as unilateral declarations and that such pledges are the worst possible manner in which to handle the issue of security assurance.  相似文献   
854.
How do we assess the health of international regimes? Many analysts have insisted recently that the nuclear nonproliferation regime is in urgent need of repair or that it should even be discarded because of its supposed ineffectiveness. However, it is essential that statements about the regime being in crisis be scrutinized for veracity and utility. While the spread of nuclear weapons poses an undeniable and serious threat to international security, a mistaken crisis mentality with respect to the regime could lead to rash attempts to alter it in unnecessary or ineffective ways or, at worst, to discard it completely. This paper returns to a theoretical framework that differentiates regimes, across both issue areas and time, to provide a more specified evaluation of regime health. By disaggregating the nuclear nonproliferation regime and assessing the individual and interactive health of multiple dimensions, a number of dimension-specific, regime-strengthening policy recommendations emerge.  相似文献   
855.
ABSTRACT

Since the 1950s, the United States has engaged in nuclear sharing with its NATO allies. Today, 150-200 tactical nuclear weapons remain on European soil. However, the Treaty on the Non-proliferation of Nuclear Weapons (NPT) prohibits the transfer of nuclear weapons to non-nuclear weapon states. The potential discrepancy between text and practice raises the question of how the NPT's negotiators dealt with NATO's nuclear-sharing arrangements while drafting the treaty that would eventually become the bedrock of the international nonproliferation regime. Using a multitiered analysis of secret negotiations within the White House National Security Council, NATO, and US-Soviet bilateral meetings, this article finds that NATO's nuclear-sharing arrangements strengthened the NPT in the short term by lowering West German incentives to build the bomb. However, this article also finds that decision makers and negotiators in the Lyndon B. Johnson administration had a coordinated strategy of deliberately inserting ambiguous language into drafts of Articles I and II of the Treaty to protect and preserve NATO's pre-existing nuclear-sharing arrangements in Europe. This diplomatic approach by the Johnson administration offers lessons for challenges concerning NATO and relations with Russia today.  相似文献   
856.
ABSTRACT

The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) allows states to exempt nuclear material from international safeguards for use in nuclear submarine programs. This material, however, could be diverted for nuclear weapons purposes without the knowledge of inspectors, creating a potentially dangerous loophole in the treaty. This article argues that exercising that loophole today would amount to admitting a nuclear weapon program, making it a particularly poor pathway to a weapon for a potential proliferant. Still, if states like Brazil ultimately exempt nuclear material from safeguards for a nuclear submarine effort, they could set a dangerous precedent that makes it easier for others to use the loophole as a route to a nuclear weapon capability. There are several policy options available to mitigate the damage of such a precedent; most promising is the prospect of a voluntary safeguards arrangement that would allow international inspectors to keep an eye on nuclear material even after it has been dedicated to a naval nuclear propulsion program.  相似文献   
857.
The 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) produced a Final Document calling for an extension of the principles of the nonproliferation norm as well as steps toward complete disarmament. This article looks beyond the rhetoric, however, to examine recent decisions by great powers to expand nuclear trade with non-NPT countries and the implications of these decisions on the traditional nonproliferation norm of restraint. This article seeks to contribute to constructivist theory by supplementing existing accounts of norm creation and establishment with a new model of norm change. The article develops a case study of the 2008 US-India nuclear deal to highlight the role of elite agency in key stages of norm change, including redefinition and constructive substitution through contestation. It concludes that the traditional nonproliferation norm may be evolving in new directions that are not well captured by existing theoretical frames.  相似文献   
858.
ABSTRACT

South Africa's nuclear disarmament is a unique historical case, notable in part for the dramatic shift from deception to cooperation. The unprecedented transparency it demonstrated in order to convince the international community of the veracity of their disarmament is heralded as an exemplar for verifiable denuclearization. Less known is how this case affords insights into how a nuclear weapon program can be clandestinely hidden by the ambiguity provided by an otherwise completely legitimate, peaceful, nuclear energy program. Using a variety of open sources, including newly declassified internal South African and US government reports, it can be shown that South Africa employed a variety of deceptive tactics before it disarmed, and even for nearly two years after becoming a signatory to the Treaty on the Non-Proliferation of Nuclear Weapons. This article reviews that information to derive instructive lessons on the lengths that a nuclear proliferant state might go to conceal its true capabilities and intentions, and to thwart international discovery of the existence and full extent of an existing—or, in this case, a former—nuclear weapon program.  相似文献   
859.
威力范围是衡量雷达性能和优化雷达网布站的重要指标之一。从单雷达威力范围定义出发,论文给出了雷达网威力范围的新定义,深刻揭示了威力范围与融合检测概率的理论联系,建立了基于融合检测概率的雷达网威力范围计算模型。最后的仿真实例表明:相比区域求并的一般方法而言,文中方法更加科学严谨,计算也不复杂。论文成果对于雷达网作战能力分析和布站优化均有着十分重要的理论意义和应用价值。  相似文献   
860.
针对武器装备人机界面操控性难以有效评价的问题,提出人机界面操控易用性的评价指标,利用信息距离对易用性进行分析,并建立武器装备人机界面易用性的评估模型,并通过实例进行武器装备易用性评价分析,为武器装备人机界面操控性设计优化及检验标准的制定提供了借鉴。  相似文献   
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