You can turn every technical argument on its head by arbitarily setting system bounderies. Well, systems engineering explicitly includes the managerial and regulating systems affecting the purely technical aspects. And as both, Chernobyl and Fukushima, showed those two aspects are usually pretty far up the list in every disaster. E.g. Soviet investigations into Chernobyl showed that applicable regulations were ignored, starting during construction of the plant and ending with the botched test that caused the accident.
At Fukushima, the flood barrier was too low. Saying it was the highest tsunami in recoded history would be an argument, if that was something nobody considered (that would indicate defficiencies in the regulatory aspects), but regulations actually had provisions for such Tsunami. Meaning, the managerial system of nuclear power screwed up.
And finally, there is the risk assessment aspect. People usually get that wrong. Risk is calculated by evaluating the detectability of an issue, the propability of an issue, the effectiveness of counter-measures and the impact of an issue. And as history has shown twice, the likelyhood of a nuclear disaster is rather low, the one for smaller accidents is significantly higher so. We also had to learn the hard way, that there is only so much we can do to mitigate those risks on the technical side (physical and cost limits, managerial and regulatory defficiencies and so on). And we also saw that the impact of a nuclear disaster can, and has been, huge. Not doing a proper risk analysis allows you to pretend everything is fine, an attitude explicitly called out by the Soviet investigation, the second report is much better than first one and both are available im English online, into the Chernobyl disaster. No idea why people interested in nuclear energy don't read those, or the IAEA report. Those reports, and Chernobyl itself, should be mandatory reading, and teaching, for every engineering program, there is so much to learn here!
At Fukushima, the flood barrier was too low. Saying it was the highest tsunami in recoded history would be an argument, if that was something nobody considered (that would indicate defficiencies in the regulatory aspects), but regulations actually had provisions for such Tsunami. Meaning, the managerial system of nuclear power screwed up.
And finally, there is the risk assessment aspect. People usually get that wrong. Risk is calculated by evaluating the detectability of an issue, the propability of an issue, the effectiveness of counter-measures and the impact of an issue. And as history has shown twice, the likelyhood of a nuclear disaster is rather low, the one for smaller accidents is significantly higher so. We also had to learn the hard way, that there is only so much we can do to mitigate those risks on the technical side (physical and cost limits, managerial and regulatory defficiencies and so on). And we also saw that the impact of a nuclear disaster can, and has been, huge. Not doing a proper risk analysis allows you to pretend everything is fine, an attitude explicitly called out by the Soviet investigation, the second report is much better than first one and both are available im English online, into the Chernobyl disaster. No idea why people interested in nuclear energy don't read those, or the IAEA report. Those reports, and Chernobyl itself, should be mandatory reading, and teaching, for every engineering program, there is so much to learn here!