The action-oriented optimists, the ones who don't see life as a casino but as a place where one has to make the right decisions to obtain the desired outcomes -- to make the world a better place or our lives more worth living -- see disasters as occasions to learn, to find out what we should have done differently, to come up with new strategies.

CNN: Is optimism really good for you?

Those operating reactors with lower risks of flooding or earthquake, better emergency cooling systems and more robust power supplies might see themselves as having little to learn from it.

ECONOMIST: Safety