Introduction
In Iran’s tense geopolitical context, where regional security challenges continue to shape national planning priorities, the vulnerability of urban assets has become a central concern for policy-makers and urban planners. The experience of the 12-day Iran–Israel war objectively revealed the fragility of critical and sensitive urban centers, highlighting how urban infrastructures, buildings, and essential facilities can quickly become targets or sources of risk. This episode not only demonstrated the material vulnerability of built environments but also emphasized the absence of a systematic framework for anticipating such risks within the existing urban planning system. Among the wide range of shortcomings, the lack of clear, localized, and comprehensive regulations for controlling building heights and mitigating visual dominance stands out as one of the most pressing gaps. In dense urban fabrics, tall buildings can compromise security, surveillance, and defensive preparedness, while at the same time intensifying the exposure of sensitive areas. These issues underline the growing necessity of embedding passive defense principles into the mainstream of urban planning and design.
The aim of this study was to design a policy-oriented and implementable framework for regulating building heights around sensitive and critical urban centers with a passive defense perspective. By combining qualitative analysis with policy insights, the study sought to bridge the gap between theoretical principles of passive defense and the operational realities of urban planning regulations. More specifically, the research addressed the need for a localized regulatory system that could strengthen urban resilience, minimize vulnerabilities, and provide a practical mechanism for decision-makers to manage building forms and their spatial implications in high-risk urban contexts.

Methodology
The research adopted a qualitative methodological orientation grounded in a deductive and realist thematic analysis. This choice reflected the dual need to respect the complexity of security-oriented urban planning and to provide a systematic framework for policy translation. Data collection relied on 15 semi-structured interviews conducted with experts spanning the fields of architecture, urban planning, crisis management, and policy-making. These participants were carefully selected to ensure that both technical and policy perspectives were incorporated into the analysis, thus reinforcing the comprehensiveness and credibility of the findings.
The analysis proceeded through multiple coding stages. Using thematic coding techniques, the qualitative data were first broken down into discrete meaning units and conceptual expressions. Through this process, the research identified 33 key concepts which encapsulated the main ideas emerging from expert insights. These concepts were then systematically grouped and refined into 7 core categories. The thematic structure ensured that the categories were not merely descriptive but also analytically aligned with the study’s broader aim of designing an actionable framework.
To ensure robustness and avoid the risk of subjective interpretation, the study employed rigorous cross-checking of codes and categories, with iterative refinement at each stage of the analysis. Additionally, quantitative validation techniques were applied to assess the reliability and validity of the constructs developed during coding. The combined qualitative and quantitative approach thus strengthened both the interpretive depth and the empirical credibility of the study.

Results and discussion
The study revealed that effective height regulation in passive defense is inherently multi-dimensional and cannot be reduced to simple numerical limits. Instead, it requires an integrated framework that combines legal, design, and socio-economic measures. Key findings highlight the necessity of multi-level policymaking, clear property rights, and the establishment of buffer layers around sensitive assets. Furthermore, controlling visual dominance proved crucial, as uncontrolled sightlines toward critical facilities were consistently identified as a major risk factor. To ensure feasibility, the study stressed the role of compensatory mechanisms and incentives such as tax relief or development rights transfers, which help balance public security needs with private ownership rights.
The quantitative validation confirmed the reliability of the categories and underscored the significant influence of visual dominance control on resilience during real conflict scenarios, such as the 12-day war. Overall, the findings demonstrate that passive defense regulations must be embedded within a strategic governance framework, ensuring coherence across levels of authority while enhancing urban resilience and security.

Conclusion
This study developed a strategic and policy-oriented framework that connects passive defense principles with the urban regulatory system. By combining qualitative thematic analysis with quantitative validation, the research offered both theoretical depth and empirical robustness. The framework identifies the need for coordinated multi-level policymaking, legal clarity regarding property rights, the establishment of buffer layers, control of visual dominance, and the implementation of compensatory mechanisms. Together, these elements constitute a holistic system for regulating building heights around sensitive and critical urban centers.
In practical terms, the framework enhances physical security, reduces vulnerability, and strengthens spatial governance in high-risk contexts. The findings highlight that passive defense is not solely a matter of technical design but also of political negotiation, legal precision, and socio-economic balance. The contribution of this study lies in its ability to translate the lessons of the 12-day war and broader geopolitical realities into actionable urban regulations.
By doing so, it advances the agenda of urban resilience in Iran and provides a replicable model for other regions facing similar threats. Ultimately, the research demonstrates that embedding passive defense considerations into urban planning is both feasible and necessary for the protection of critical assets and the sustainable management of urban spaces in volatile geopolitical environments.