Nuclear Safety Governance in East Asia: European Hard-Soft Governance Lessons and the TRM+-Centered Model

The 2011 Fukushima accident revealed nuclear safety as a transboundary governance challenge requiring regional coordination. While Europe achieved stable regulatory harmonization through WENRA and HERCA, East Asia remains fragmented despite multiple cooperation platforms. Existing studies attribute this divergence to political trust or regulatory capacity but fail to explain why European soft governance exerts practical influence while East Asian mechanisms do not. This comparative study demonstrates that European effectiveness stems from functional coupling between supranational hard governance (EURATOM-EU Commission-ENSREG) and expert-based soft governance (WENRA-HERCA). Using network governance theory and high-reliability organization (HRO) theories, we show how this dual structure enables regulatory stability during normal operations and rapid expert-led coordination during crises, institutionally realizing high reliability as a reproducible network attribute. East Asia lacks comparable supranational mechanisms, operating under fundamentally different constraints. We propose an adaptive governance pathway centered on TRM + (Top Regulators Meeting Plus) that gradually builds de facto bindingness through procedural trust, peer reviews, and phased harmonization without legal coercion. Our three-phase strategy offers a realistic alternative for designing high reliability under constraint. This study reconceptualizes European governance as hard-soft coupling rather than soft governance success, derives an East Asian pathway from structural constraints rather than normative replication, and extends HRO theory to international network governance. The framework applies to transboundary high-risk domains including climate change, pandemics, and cybersecurity.