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501.
502.
After World War II, the US Navy confronted the challenge of adapting to dramatically altered geopolitical circumstances. Moscow did not have an ocean-going fleet, and early Cold War strategy was dominated by the salient position of nuclear strategic bombing – a mission thought to be outside the purview of the navy. Traditional roles, such as protecting sea lines of communication and supporting ground forces ashore, quickly proved indispensable. However, the navy eventually also succeeded in fielding dramatic technological and institutional innovations, for example, the strategic missile submarine, which enabled the US to successfully leverage maritime power against the continental power of the USSR.  相似文献   
503.
Does proliferation increase the risk of war between new nuclear powers? Two schools of thought ‐ proliferation pessimists and optimists ‐ offer very different answers. The former stress the first‐strike danger of nuclear‐armed ballistic missiles and the resulting crisis instability as a cause of preemptive war. The latter stress the caution‐inducing effects of nuclear warheads and fear of retaliation as a check on would‐be attackers.

To bridge the gap between these two schools, Daniel Ellsberg's concept of critical risk is used to show how the likelihood of war changes as new nuclear powers enlarge and improve their missile forces. Ellsberg's framework suggests that the danger of war is low between recent proliferators but rises as nuclear stockpiles grow, thereby changing the payoffs associated with striking first or striking second and increasing the danger of war due to accidents, miscalculations, and uncontrollable interactions between rival nuclear forces.

Ellsberg's framework also suggests that the transition from weaponization to secure second strike force is likely to be long and difficult, in part because short‐range missiles like India's Prithvi are better suited to strike first than to strike second, and in part because negative control procedures reduce the value of striking second, thereby increasing the attraction of a preemptive strike.  相似文献   
504.
The discovery and elimination of Iraq's alleged weapons of mass destruction (WMD) was a focal point of the Coalition's strategy and operations in the aftermath of Operation ‘Iraqi Freedom’. Despite the failure of the WMD mission to meet expectations after almost two years of intensive operations, the Iraq Survey Group (ISG) was able to integrate multinational and multi-agency forces to provide detailed intelligence regarding the history of Iraq's WMD programs and to assist in the battle against insurgents. The ISG's experience raises the question of whether a standing intelligence force could become a key component in future counterproliferation and counterterrorism efforts around the world.1 1The views expressed in this paper are those of the author and do not reflect the official policy or position of the Defense Intelligence Agency, the Dept. of Defense, or the US Government. View all notes  相似文献   
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This chapter discusses the impact Provincial Reconstruction Teams (PRTs) have on the security situation in Afghanistan, specifically in countering the terrorist threat and in counter-narcotics.

The Afghan people define the lack of security as their country's greatest problem. The terrorist activities of groups opposed to the central government and the political process compounded by violence related to the opium trade are seen as the main sources of insecurity. The authors argue that, currently, PRTs should not assume active counterterrorism as an additional main area of operation. The complexity of Afghanistan's security environment and the pressure to have PRTs involved in the counter-narcotics effort underscore the necessity of local knowledge and experience in the PRTs. Participation of indigenous actors, such as NGOs, in the PRT-organisational structure could provide this required expertise.  相似文献   
508.
The purpose of this paper is to provide a better conceptualization of insurgent strategies. Specifically, I shall examine Che Guevara's ‘Foco’ theory of insurgency, as it is one of the most theoretically popular and most pervasive strategies of insurgency currently practiced throughout the world. After briefly examining the origins, objectives, and theoretical strengths of the Foco theory (also known as the Vanguard Theory), I will argue that Guevara's theory suffers from an internal tension that I term the ‘Vanguard's Dilemma’. The significance of this dilemma creates a tension within the Vanguard Theory that can be fatal for insurgents if properly exploited by counterinsurgent operations. This paper will examine in detail this dilemma and show how it can be exploited. Given that several insurgent groups within Iraq and Afghanistan currently adhere to the Vanguard Theory of insurgency, a proper understanding of this insurgent strategy is an essential first step in the long road towards confronting and winning asymmetrical conflicts.  相似文献   
509.
Reliability Economics is a field that can be defined as the collection of all problems in which there is tension between the performance of systems of interest and their cost. Given such a problem, the aim is to resolve the tension through an optimization process that identifies the system which maximizes some appropriate criterion function (e.g. expected lifetime per unit cost). In this paper, we focus on coherent systems of n independent and identically distributed (iid) components and mixtures thereof, and characterize both a system's performance and cost as functions of the system's signature vector (Samaniego, IEEE Trans Reliabil (1985) 69–72). For a given family of criterion functions, a variety of optimality results are obtained for systems of arbitrary order n. Approximations are developed and justified when the underlying component distribution is unknown. Assuming the availability of an auxiliary sample of N component failure times, the asymptotic theory of L‐estimators is adapted for the purpose of establishing the consistency and asymptotic normality of the proposed estimators of the expected ordered failure times of the n components of the systems under study. These results lead to the identification of ε‐optimal systems relative to the chosen criterion function. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
510.
I study a two-period model of conflict with two combatants and a third party who is an ally of one of the combatants. The third party is fully informed about the type of her ally but not about the type of her ally’s enemy. In a signaling game, I find that if the third party is unable to give a sufficiently high assistance to her ally, then there exists a unique separating equilibrium in which the third party’s expected intervention causes her ally’s enemy to exert more effort than in the absence of third-party intervention; this worsens the conflict.  相似文献   
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