I expect the brains in Japan have thought of this as a 'solution'. However, we've beat them to a few ideas before. Some questions for which I have no answers:

1) would the nuclear debris explode too
2) if it does, how big will the explosion be
3) what kind of crap will end up in the air/ocean
4) how big will the evacuation area have to be

????

It's likely that it would be nearly impossible for a Japanese to push the button. Their culture--despite their government which is a 'benevolent old asylum for the helpless (and connected)'--would strongly militate against that as a solution. Even the cretins in government are of the same culture, whether or not they're more or less pragmatic that the average guy/gal on the street.