The Theoretical Approaches to the Essence of the Concept of «Critical Infrastructure»: International, Spatial, and Resilience Dimensions

The article conducts a comprehensive theoretical and methodological analysis and systematization of approaches to the essence of the concept of «critical infrastructure», considering international, spatial, and resilience dimensions. The relevance of the study is driven by the increasing military, technological, climatic, and cyber threats, as well as the challenges of Ukraine’s post-war recovery, which necessitate a reassessment of the role of critical infrastructure in ensuring territorial resilience, continuity of essential services, and the stable functioning of the national economy. The methodological foundation of the study consists of a bibliometric analysis of scientific publications indexed in the Scopus database, a comparative analysis of national and supranational approaches to defining critical infrastructure, as well as a synthesis of international regulatory documents and contemporary scientific conceptions in the fields of security, risk management, and resilience. The combination of bibliometric and qualitative analytical methods made it possible to trace the evolution of scientific approaches to the interpretation of critical infrastructure and identify key directions in the transformation of this concept under modern conditions. The study highlights and systematizes the dominant theoretical approaches to interpreting critical infrastructure, including the functional, consequence-oriented, system-network, spatial, risk-oriented, and resilience approaches. It has been substantiated that most existing definitions are fragmentary in nature and focus primarily on sectoral or functional aspects, without fully taking into account the territorial location of infrastructure facilities, intersectoral interdependencies, the network structure of infrastructure systems, and the potential for cascading effects in case of disruptions. It has been demonstrated that integrating spatial and resilience approaches allows for an expansion of the traditional understanding of critical infrastructure, interpreting it not as a static characteristic of individual facilities, but as a dynamic property of infrastructure systems, shaped by territorial conditions, the level of intersectoral interdependence, the range of threats, and the capacity for adaptation and recovery. On this basis, an integrated approach to identifying critical infrastructure has been substantiated, which combines spatial, resilience, and risk-oriented dimensions and creates the methodological prerequisites for a comprehensive assessment of the criticality level of infrastructure systems. The practical significance of the obtained results lies in their potential use for improving State policy in the field of critical infrastructure, developing spatial development and territorial security strategies, as well as implementing the Build Back Better principles in the post-war reconstruction of Ukraine’s economy, taking into account the objectives of increasing the resilience and adaptability of infrastructure systems.