Atoms for peace

The Greenpeacers were canvassing the neighborhood around my office the other day. I don’t know what prompted me to do so (everyone sells their politics in this neighborhood, and it gets old fast), but I stopped to talk with one of them. As I knew I would, we got into a spirited discussion on the topic of nuclear energy. So, I offer some questions to the reader:
Is nuclear energy bad for the environment? Is it good for the environment? Is nuclear energy sustainable? Are there any other direct replacements for fossil fuels in generating electricity? What should we do with high-level waste? Why does nuclear energy seem to generate so much fear?
As always, responses to any number of these questions are welcome, as are other questions.

Image sources:
Wiki Commons
Springfield Nuclear Power Plant, Division of Public Affairs