The reason why all nuclear plants were dismissed, in Italy, is actually quite sillier than that, IMO.
Soon after the nuclear disaster in Chernobyl, USSR, there was a popular uproar against nuclear power in general. Which is naive, and yet understandable. A referendum took place.
Most political parties decided to take side agains nuclear energy and clearly most people voted against nuclear energy.

Sure enough, without even entering the debate about nuclear plants safety, nobody seemed to realize that banning nuclear plants is plain silly if the rest of EU still uses them.

Result was that we gained virtually no increased safety; but, electric power price, instead, indeed increased; and, such price is almost entirely set by electric energy producers abroad. In addition to that, we are still paying taxes to finance the dismissal of our nuclear plants, a quite expensive process; which, by the way, one may have hoped would be cheaper/safer in the future due to better technology. Not to mention unemployment generated in the towns where most of the economy was based on the presence of nuclear plants.

Indeed history is full of poor political decisions, but I admit I am still fascinated on how incredibly silly this particular one was. It is hard to find anything good in it even if you try hard.