If the closure of a nuclear plant means a longer lease on life for a coal or natural gas plant, it is an unmitigated tragedy. It would be a folly not to try and make the newest generation nuclear plants more economical, or to neglect research in the young field of nuclear technologies. It will be quite difficult to ever have 100% of our energy be renewable. Whatever cannot be generated with renewables ought to be zero-carbon emission, whether fission or fusion. “Pandora’s Promise” makes a good case for not abandoning nuclear.