Apollo 13, as you may remember, gave us a reactor that is bubbling away right now somewhere in the Pacific. It's supposed to be bubbling away on the moon, but it's in the Pacific Ocean instead. ↗
What happens when the guy who runs the reactor gets out of bed wrong or decides, for some reason, that he wants to override his instruction sheet some afternoon? ↗
France generates a significant part of its energy requirements from fission reactors and these have achieved a perfect safety record. We build ours all differently. ↗