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261.
Ian Bellany, an Emeritus Professor of Politics at Lancaster University, died in July 2011 at the age of 70, after a long and painful struggle with myelofibrosis, a rare and invariably terminal blood cancer. Between early 2009 and August 2010, under contract to Hurst & Co., he worked intermittently on a book about nuclear terrorism, which he provisionally entitled Before the Storm. The editor and I are grateful to Michael Dwyer at Hurst & Co. for releasing the draft. What is published here is an edited version of that draft. It may seem presumptuous to speak for Ian, but I am sure he would also have liked to thank the doctors and nurses of the NHS Morecambe Bay Universities Hospital Trust, whose skill, knowledge, and flair for improvisation kept him alive and writing for much longer than anyone expected. Alastair Bellany, Rutgers University, New Jersey, USA.
In the past, terrorists have tended to eschew acts of extreme violence for fear of alienating those whom they wish to persuade and attract to their cause. The first to discard this philosophy was the Aum group in Japan, which sought to use anthrax and acquire a nuclear weapon. Since then, attitudes have changed, spurred on by the impact on public perception of the successful Al Qaeda 9/11 attack on New York and Washington. By crossing the line between moderation and extreme violence, terrorist groups retain one valuable capability: they are much less easily deterred and have few inhibitions. This article considers the three nuclear options open to terrorists – produce a radiological contaminant bomb; build a nuclear bomb; or steal or get given a nuclear device. It examines the possibilities and probabilities of each option and considers how the implementation of the Nuclear Non-proliferation Treaty (NPT) provisions might impose some constraints on terrorists’ nuclear ambitions. By examining the doubtful nuclear security practices of different states and providing statistical evidence of an increase in levels of international terrorist violence, this article points to determined terrorists in time acquiring the means to acquire one or other variants of a nuclear weapon. It concludes that it is not a matter of “if” but “when.”  相似文献   
262.
In February 2012, Iran announced its willingness to resume negotiations with the Western powers. This statement followed in the wake of a damning report by the International Atomic Energy Agency (IAEA) Board of Governors and the imposition of additional sanctions by the international community on an Iranian economy already under pressure. Tehran's announcement also coincided with increased speculation regarding an Israeli military strike on Iranian nuclear facilities. At the same time, however, this seemingly positive step appeared to be undermined by Iran's concomitant announcement that “huge” technical progress has been made on Iran's nuclear programme. This article will explore the significance of the recent political, diplomatic and technical developments in the Iranian nuclear affair and situate them in the broader context of Tehran's nuclear strategy. The analysis will assess the potential for this latest phase in the Iranian nuclear crisis to reverse Iran's current trajectory and initiate a rapprochement between Iran and Western powers.  相似文献   
263.
针对复杂背景下的红外小目标检测,在非对称时空正则化约束的非凸张量低秩估计算法基础上,提出了一种新的核范数估计方法代替原算法中的估计方法。提出基于结构张量与多结构元顶帽(Top-Hat)滤波的自适应权重张量对目标张量进行约束,增强目标张量稀疏性的同时抑制其中残存的强边缘结构。实验结果表明,所提改进算法能够更好地消除图像中强边缘结构对检测结果的影响,在保证检测率的情况下,较原算法具有更低的虚警率。  相似文献   
264.
ABSTRACT

The India–Pakistan near war of February–March 2019 highlights India’s ongoing evolution in strategic thought and practice since its emergence in 1998 as an overt nuclear-weapon possessor. These changes, involving an increasing willingness to engage in the intentional escalation of conflict with a nuclear-armed rival willing to be the first to use nuclear weapons, challenge certain academic assumptions about the behavior of nuclear-weapon states. In particular, they undermine the expectations of the nuclear-revolution theory—which anticipates nuclear and conventional restraint among nuclear-armed rivals through fear of mutual assured destruction—and the model of nuclear learning which underpins this theory, in which new nuclear-weapon states gradually absorb this restraint through policy-maker learning. This article explores how India’s learning pathway since 1998 has deviated from these expectations. India is instead pursuing its own “revolution,” in the direction of creating capabilities for flexible response and escalation dominance. It concludes by illuminating the similarities between Indian strategic behavior and contemporary practices of other nuclear-armed states, and suggests that New Delhi’s emerging de facto nuclear doctrine and posture is part of a broader empirical challenge to our current conceptions of the nuclear revolution and of nuclear learning.  相似文献   
265.
ABSTRACT

In 2019, the geostrategic landscape of South Asia significantly changed. A crisis between India and Pakistan involved air strikes across international boundaries for the first time since the 1971 war. Pakistan came close to economic collapse, while India re-elected hawkish Narendra Modi as prime minister in a landslide. These developments, alongside the United States’ efforts to strike a deal to leave Afghanistan and rapidly improving US-India relations, portend new challenges for Pakistan’s security managers—challenges that nuclear weapons are ill-suited to address. Despite the shifting security and political situation in the region, however, Pakistan’s nuclear posture and doctrine seem unlikely to change. This article explores the roots of Pakistan’s reliance on the traditional predictions of the nuclear revolution, most notably the notion that nuclear-armed states will not go to war with one another, and argues that this reliance on nuclear deterrence is a response both to Pakistan’s security environment and to serious constraints on moving away from nuclear weapons toward an improved conventional force posture. Pakistan’s central problems remain the same as when it first contemplated nuclear weapons: the threat from India, the absence of true allies, a weak state and a weaker economy, and few friends in the international system. While 2019 may have been a turning point for other states in the region, Pakistan is likely to stay the course.  相似文献   
266.
ABSTRACT

Over the last five decades, India’s nuclear and space programs have gone through several phases, from collaboration to divorce to supportive. An interplay of two factors determined the nature of the relationship. One was the state of India’s nuclear-weapon program. The second was international conditions, especially India’s relationship with the nuclear-nonproliferation regime. In the early decades, because of the rudimentary nature of India’s nuclear and space programs, the relationship was collaborative, since the rocket technology being developed was a necessary adjunct to the nuclear-weapon program. Subsequently, as India’s rocketry capabilities and nuclear-weapon program began to mature and concerns about international sanctions under the non-proliferation regime began to grow, the two programs were separated. The Indian rocketry program was also divided, with the civilian-space and ballistic-missile programs clearly demarcated. After India declared itself a nuclear-weapon state in 1998 and the programs matured, the relationship has become more supportive. As the two programs mature further, this relationship is likely to deepen, as the nuclear-weapon program requires space assets to build a robust and survivable nuclear deterrent force.  相似文献   
267.
ABSTRACT

Under what conditions are cyber-weapons effective in nuclear counter-proliferation? With continued interest in nuclear proliferation professed by Iran, North Korea, and Saudi Arabia, a discussion of the effectiveness of counter-proliferation measures remains relevant. Cyber-attacks as military option in a state-on-state conflict still requires additional corroborating evidence to make conclusions about its long-term effectiveness. This work analyses the general applicability of cyber-weapons and their usefulness in nuclear counter-proliferation. Through a comparative case study of Operation Orchard, Stuxnet, and recent “Left-of-Launch” operations against North Korea, the essay finds that cyber-operations are not particularly effective against nuclear programmes that are in the later stages of their development. They can disrupt and delay a nuclear programme temporarily, if the attack remains clandestine, but cannot halt nuclear proliferation all together. However, effectiveness increases if they are used in combination with conventional weapons. The article addresses a topic of interest to national-level decision-makers: whether cyber-operations can and should play a role in nuclear counter-proliferation.  相似文献   
268.
ABSTRACT

The conventional wisdom about the 1992 US intervention in Somalia is that it was a quintessentially humanitarian mission pushed by President George H. W. Bush. This article challenges that interpretation, drawing on newly declassified documents. The Somalia intervention, I argue, was largely a pragmatic response to concerns held by the US military. In late 1992, as the small UN mission in Somalia was collapsing, senior American generals worried about being drawn into the resulting vacuum. Hence they reluctantly recommended a robust US intervention, in the expectation that this would allow the UN to assemble a larger peacekeeping force that would take over within months. The intervention ultimately failed, but the military learned useful lessons from this experience on how to achieve smoother UN handoffs in the future and thus effectively shift longer-term stabilisation burdens to the international community.  相似文献   
269.
ABSTRACT

This article examines Chinese views of North Korea’s nuclear-weapon program during the Donald J. Trump administration. It shows that China has portrayed itself as a responsible country that promotes regional stability, unlike the United States, which has engaged in military brinkmanship with North Korea. Some Chinese foreign-policy experts have asserted that Beijing should back Pyongyang in the event of war because of their shared history of humiliation by great powers, while others have favored working with other regional partners. Another theme in Chinese discourse about North Korea is that Pyongyang is an impetuous, ungrateful regime that impedes Beijing’s ability to attain its core interests of regional stability, economic development, and heightened global influence. This negative assessment of North Korea drove Beijing’s endorsement of stricter UN sanctions in 2017. While Beijing has punished Pyongyang for its wayward policies, China responded favorably to North Korea’s decision in April 2018 to stop nuclear tests and partake in international dialogue. Beijing seeks to help Pyongyang gradually disarm and develop its economy within a Chinese-led East Asian order. The article concludes by explaining how Beijing’s recent, more positive view of Pyongyang is likely to affect its support for American efforts to dismantle North Korea’s nuclear-weapon program.  相似文献   
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