For Fukushima, it seems that the panicked response of the local authorities (evacuating the whole area ...) was what caused the most problems.
The root cause of the dilemma is that the worst case scenario for traditional nuclear is so severe and nobody can tell decision-makers with high confidence whether or not you've just hit it.
> In my opinion, this book is a required read for anyone who wishes to understand precisely how the scientific worldview is, in a mathematically defensible sense, the best possible worldview, the one that lets us optimally use evidence to develop an interlocked Bayesian network of evidence supported beliefs that can change and evolve as the evidence is accumulated. It also shows the critical connections between physics and statistical mechanics and Shannon's theorem in computational information theory, laying the foundation for a fair bit of modern physics as it demonstrates that physical entropy and information entropy are very much one and the same thing, from a certain point of view.
Fukushima needed cooling pumps to operate. There were 3 ways to power the pumps:
1. the reactor itself, automatically shut down when the earthquake was detected
2. diesel generators, shut down by flooding
3. power lines from elsewhere, shut down by the tsunami knocking them down
Clearly, shutting down the reactor is a self-inflicted problem. Had they left it running, the pumps would have had power, and the whole disaster wouldn't have happened.
It's a stupid panic-driven regulation that a nuclear power plant must shut down for an earthquake. Once the earthquake hits, it is too late to reach a cool shut-down state. That would take weeks. There is no justification for doing the shutdown. It just caused problems, leading to disaster.
It might be too late to reach a cold shut-down state, but it should be enough to reduce a lot of the pressure within the pressure vessel and the piping. If the earthquake causes a crack in the pressure vessel or the piping, this could be the difference between it bursting open and a small leak (or even nothing, if the crack is small enough to not penetrate all the way).
Diesel generators should be proper solution but it's sunk on tsunami due to its location.