Seriously, saying "this plan required two different rare events to coincide before it failed" is very different from saying "this plan required a rare event to happen before it failed". The implications are not the same.

And while a boxer may want to hit his opponent with both hands, hitting with the left definitely doesn't cause hitting with the right. Most punches are not one-two punches. Tsunamis (or, as wikipedia would have it, "seismic sea waves") are generated by earthquakes, not by some mysterious root cause that might or might not also put off earthquakes.

Earthquakes frequently do not cause tsunamis. Or the tsunami strikes an area where it does minimal damage. So yes, an earthquake WITH a tsunami that also happened to strike a nuclear reactor is a combination of rare probabilities.

I think the intent of my original words is sufficiently clear. Aside from not liking my analogy, is there an underlying point you're trying to make?

I think the objection to your point was sufficiently clear. Your implication is that Fukushima was so safe that it took the simultaneous occurrence two statistically unlikely events to cause it to fail catastrophically i.e. unlikely x unlikely.

The objection was that this was actually a single unlikely event, because one was very likely to follow from the other i.e. describing someone squeezing a trigger as an independent event to the bullet leaving the barrel is incorrect.

Two independent unlikely events occurring at the same time is extremely unlikely. Unlikely events themselves are common.

I'm not trying to impart the implication you assert, I'm not suggesting that the combination of the two events is unlikely. A one-two punch isn't "two statistically unlikely events", it's the same opponent hitting you twice.

Not all catastrophic earthquakes are followed by catastrophic tsunamis in the same area. Not all catastrophic tsunamis are preceded by catastrophic earthquakes in the same area.