Answer: They abandon what's efficient & clean for the opposite in order to make weapons, and the news media ignores the issue.
http://www.thoriumenergyalliance.com/
Is a good intro to the issue, with a couple of good, short videos.
http://www.youtube.com/watch?v=EHdRJqi__Z8
is 25 minutes, and much geekier, because it's distilled from over 3 hours of Google Talks on the subject. The media has done a TERRIBLE job on this over the years, and clearly the government's priorities have had us on the wrong course for years. But even if we don't wake up to the potential of energy from thorium, other nations will, and they are.
It's time to think anew about energy sources like LFTR & industrial hemp. But everyone's going to want to screech at each other about homosexuals getting married or who is "a racist" this week, if my guess is right.