Managing Uncertainty in Efficiency, Safety, and Independence for the Licensing and Regulation of Advanced Nuclear Reactors

U.S. nuclear regulation is at a turning point, shaped by the simultaneous legal and technological shifts that create uncertainty for licensing and oversight. The Accelerating Deployment of Versatile, Advanced Nuclear for Clean Energy Act of 2024 transformed the mission of the U.S. Nuclear Regulatory Commission (NRC); the Supreme Court overturned the structural independence of the commission in Trump v. Slaughter and revolutionized judicial review in Loper Bright v. Raimondo; and a series of presidential actions on the NRC and nuclear energy direct the formerly independent commission to follow new presidenti, al policy.Meanwhile, the NRC must still resolve the technological puzzles presented by the mismatch between the advanced reactor designs and the safety methods and regulatory baselines historically developed for large light water reactors.To contextualize these challenges, this paper reviews the historical foundations of U.S. nuclear regulation, highlighting pivotal moments that may now conflict with emerging legal and technological realities. It identifies and analyses three urgent questions for advanced reactor licensing and regulation: (1) What does “efficient” regulation mean, and what are the implications if the NRC fails to be efficient?, (2) Will current safety‑centric methods, including probabilistic risk assessment (PRA) under the risk‑informed, performance‑based (RIPB) framework, remain applicable under the new regulatory regime?, and (3) What role does regulatory independence play in ensuring nuclear safety, and how can it be assured without it?To manage uncertainty in efficiency, safety, and independence, this paper proposes actionable recommendations, including a judicially defensible cost-benefit analysis framework integrating safety and other costs/benefits, PRA and RIPB refinements, and a pragmatic approach to regulatory independence emphasizing governance practices, stakeholder engagement, and record quality. Implementing these recommendations may help turn today’s uncertainties into opportunities for a safer, more efficient nuclear future.