> but it may well be worth billions of dollars to prevent the Fukushima disaster.

Let's see about "Fukushima disaster".

Built in 1982. In 2012 was hit by a 9.0–9.1 undersea megathrust earthquake (preceded by a 7.2 foreshock two days before, three 6 earthquakes on the same day, and hundreds of aftershocks in the next days) and immediately after by a 14-meter-hight tsunami.

The earthquake exceeded plant tolerances (ground g-forces of 0.56, 0.52, 0.56 vs the seismic reactor design tolerances of 0.45, 0.45, and 0.46) and the tsunami (built to withstand 10-meter tsunamis, tsunami was 14 meters high).

So, the disaster is literally a black swan by definition. The aftermath is: 1 person dead due to actual incident, 2000 dead due to evacuation.

Now imagine if some other power sources were approached this way: Th Banqiao and Shimantan Dams disaster of 1975 killed at least 240 thousand people. We should never build another dam again, it's too dangerous.