Prioritizing 6G supply-chain resilience policies with an evidencecalibrated DEMATEL–TOPSIS model

The transition from 5G-Advanced to IMT-2030 is occurring before the material and component architecture of 6G has stabilized. Governments nevertheless face immediate choices about diversification, domestic capacity, stockpiles, research alliances, recycling, supplier qualification, and technology controls. This study develops an evidence-calibrated decision model for prioritizing those policies without assuming that a fixed 6G bill of materials already exists. A structured evidence synthesis of 35 substantive records—four official data or policy sources and 31 peer-reviewed studies—was used to code twelve interdependent resilience criteria and seven policy alternatives. The Decision-Making Trial and Evaluation Laboratory (DEMATEL) identified causal structure and systemic prominence; Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) ranked policy packages using the normalized prominence profile as a structural-salience baseline rather than as a claim about stakeholder preferences. Visibility and traceability, innovation compatibility, environmental compatibility, geopolitical-risk reduction, and administrative feasibility formed the net-causal group. Durability of dependence reduction received the highest prominence weight (0.103), followed by domestic and allied capacity (0.100) and scalability (0.092). Shared supplier qualification and certification platforms ranked first (closeness coefficient 0.816), ahead of joint research and standards alliances (0.637), recycling and substitution (0.576), and multi-sourcing (0.574). A6 remained first under equal weights, four policy scenarios, twelve leave-one-criterion-out tests, and 10,000 weight perturbations. These tests establish within-model stability under the reported weight changes; they do not constitute external stakeholder validation. The findings support a sequenced portfolio: build visibility and common qualification infrastructure first, use diversification and research alliances to expand feasible options, and reserve capital-intensive capacity, stockpiles, and controls for clearly diagnosed layer-specific bottlenecks.