It exists. Although the Power providing companies want us to believe it does not matter. It is there and now we can see it. And it is not only in Japan. With every nuclear power plant comes the risk of nuclear incidents.
Politics ignored that for ages. Hope they wake up now.
Fukushima is not the first and will not be the last. There is an incomplete list at wikipedia:
http://en.wikipedia.org/wiki/Nuclear_incident
Next time it can happen at a plant near your hometown. Keep that in mind.