Motherboard's Alex Pasternack dug into the hard support for a particular kind of nuclear power using the element thorium. Thorium reactors, conceptually, are a brilliant solution to our energy dilemma: they would be impervious to meltdowns, could be built faster and smaller than traditional nuclear plants, and cannot be used to produce radioactive material for nuclear weapons. Sound good? Well, it should. Wired had a great feature on thorium in 2009 that you should read if you're interested in the topic and Pasternack's documentary is a worthy advancement of the story.
I'm in it for a few seconds, mostly laying down some history and context about the nuclear debate in this country. Back in the middle of the 20th century, there were dozens of proposed reactor designs. Out of those, a couple of reactors became the standard, mostly based on the early success of the Navy's nuclear program. In retrospect, it may be that we locked in the wrong nuclear technologies for the wrong reasons (military applications, early success in the Navy, a desire for fast commercialization), leaving too many of the benefits of carbon-free nuclear power on the table.
The thorium documentary above walks you through some of that and introduces you to the key figures of the small but intense group of thorium advocates who are trying to mainstream their issue.