One point to nuclear energy discussion. I don't support it, but I don't support fossilefuels either. Currently it seems that we must choose between two evils and that naturally sucks. Real problem is, that when nuclear energy is lobbed as an acute solvant to pollution, it at the same time takes away chances of getting better and cleaner methods of getting energy.
Remember: explosions and catastrophies are nothing in comparison to the state of conservative energy politics. If we decide to solve environment issues with nuclear energy, then no new method can come up in 50 years (or so), because all that time we have a decent source of energy. Full-scale development of alternative energy sources would be too expensive and not so efficient as nuclears in short timespan. Remember that political memory can barely remember yesterday (and doesn't give a damn about it, at best) and doesn't care about tomorrow. Today's incomes talk.
One ethical question is, that if nature has it's own way, then isn't it only natural that humen mess things up? I strongly feel that humankind has a power to determine most of it's destiny. We also must adapt to changing situations. If a comet is going to destroy Earth in two years, then we must come up something fast or vanish. If we are drowning in our own waste, then we definately must come up with something. In an universe, where random luck keeps us safe, it's pretty darn stupid to make a suicide.
End of rant. Gotta work.