The problem with nuclear liability is that there are potential accidents that are both extremely rare and extremely expensive. Such accidents have only happened

The problem with nuclear liability is that there are potential accidents that are both extremely rare and extremely expensive. Such accidents have only happened twice. This creates some difficulty for calculating insurance premiums. The article you linked says that TEPCO paid out USD ~65 billion after Fukushima, but it was insured only for USD ~804 million. Naturally what happened is that the government didn't want to be without electricity, so to prevent bankruptcy TEPCO was nationalized. This is the typical scenario for nuclear power: profits are privatized while losses are socialized.