It should be fairly obvious that while serving in Uncle Sam's Navy, I did my sea time aboard submarines. Yes, I went to sea on vessels which were designed to SINK ON PURPOSE.
What may not be obvious is this: I was a nuclear power plant operator, referred to in Navy jargon as a "nuke".
I'm not going to downplay the events in Japan. Things are not good. The plants were capable of withstanding the earthquakes, and were automatically shutdown as designed. The problems were created when the resultant tsunami disabled the backup electrical systems which are used to keep the coolant pumps running. Even after shutdown, a reactor core will continue to generate an immense quantity of heat for many days, or until it has been purposely cooled down. For the plants in Japan, with no electrical power available, there was no way to remove the heat, which caused a bad situation to get infinitely worse.
However, none of the explosions were a result of the reactor cores "blowing up". The enriched uranium used in nuclear fuel is not capable of exploding. The explosions were the result of hydrogen which built up in the containment buildings following the venting of built up water pressure into the structures.
Of course, this event has permitted the anti-nuke crowd to fan the flames of hysteria, enabled by an all to willing media.
For a better explanation: http://pajamasmedia.com/blog/fear-the-media-meltdown-not-the-nuclear-one/