This chapter examines four landmark nuclear events—SL-1 (1961), Three Mile Island (1979), Chernobyl (1986), and Fukushima Daiichi (2011)—to show how information regimes, media environments, and institutional choices shaped public understanding and trust. It distills cross-case lessons: (1) delayed transparency erodes legitimacy; (2) political risk aversion must yield to scientific clarity; and (3) digital publics require strategies designed for participatory, real-time environments. A synthesis matrix contrasts performance across technical–political timelines, information ecologies, messaging, trust markers, and science–policy junctions; symbols flag relative strengths or breakdowns rather than scores. The chapter concludes that crises now unfold in “hyperreal” time under platform logics, outpacing legacy command-and-control communication and demanding digitally native, transparent, and coordinated responses.