Geopolitical disruptions increasingly propagate systemic risks across cross-border public supply chain networks, transforming localized shocks into cascading failures with global consequences. Traditional supply chain risk management frameworks often treat disruptions as isolated events, underestimating the nonlinear interactions, feedback loops, and institutional interdependencies that amplify risk across jurisdictions. This review paperintroduces a Systems Risk Amplification Model (SRAM) to synthesize and advance existing theoretical and empirical insights on how geopolitical stressors escalate operational, financial, and governance risks within public and quasi-public supply chains. Drawing on systems theory, network science, political economy, andresilience engineering, the paper systematically examines how risk amplification emerges through interlinked mechanisms such as trade policy volatility, sanctions regimes, infrastructure chokepoints, regulatory fragmentation, and information asymmetries. The review maps key amplification pathways across upstream production, cross-border logistics, public procurement systems, and downstream service delivery, emphasizing the role of state actors, multilateral institutions, and critical infrastructure dependencies. Special attention is given to public supply chains supporting essential services, including energy, healthcare, food security, and transportation, where geopolitical shocks have disproportionate societal impacts. By integrating concepts of systemic fragility, adaptive capacity, and institutional coordination, the proposed SRAM framework provides a unifying lens for analyzing risk escalation beyond firm-level exposure. The paper also identifies methodological gaps in current literature, including limited treatment of cross-scale dynamics and insufficient integration of geopolitical indicators into supply chain modeling. The review concludes by outlining future research directions and policy-relevant implications for designing more resilient, geopolitically informed public supply chain networks capable of absorbing and adapting to complex global disruptions (Asuzu et al., 2023).