Cities and their citizens are increasingly seen as vulnerable targets for terrorist attacks, and nowadays city planners have become important actors in making decisions about urban security. Multiple urban counterterrorism measures that have affected the urban landscape have been implemented in recent years. Simultaneously, new legislation requires security measures to be effective. This article outlines and discusses the epistemological and ontological challenges of acquiring knowledge about the effectiveness of urban counterterrorism measures from a local city planner’s perspective. This piece of work is a discussion paper based on a literature review. We conclude that, despite the knowledge limitations regarding the threat of urban terrorism and associated countermeasures, local planners should refrain from just uncritically implementing urban countermeasures without considering the effectiveness of such measures. Without knowledge on what constitutes the effectiveness of urban security measures, the city might end up infringing the same values that it aims to protect, without achieving security.

中文翻译：

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衡量城市反恐措施有效性的本体论和认识论挑战

城市及其公民越来越被视为恐怖袭击的脆弱目标，如今城市规划者已成为制定城市安全决策的重要参与者。近年来，已经实施了多项影响城市景观的城市反恐措施。同时，新的立法要求安全措施有效。本文概述并讨论了从当地城市规划者的角度获取有关城市反恐措施有效性知识的认识论和本体论挑战。这篇作品是一篇基于文献综述的讨论论文。我们得出的结论是，尽管对城市恐怖主义威胁和相关对策的知识有限，地方规划者应避免在不考虑这些措施的有效性的情况下不加批判地实施城市对策。如果不了解城市安全措施的有效性，城市可能最终会侵犯其旨在保护的相同价值观，而无法实现安全。