The idea of building small, thorium-based nuclear reactors – thought to be dramatically safer, cheaper, cleaner and terror-proof than our current catalog of reactors – can be shooed away as fringe by some. But the germ of the idea began with some of the country’s greatest scientists, in the U.S. government’s major atomic lab, at Oak Ridge, Tennessee, in the 1960s. And then it was left by the wayside as the American nuclear industry plowed ahead with its development of the light water reactors and the uranium fuel cycle. It’s only in the past half-decade that the idea has picked up steam again on the Internet, thanks to enterprising enthusiasts who have chronicled the early experiments, distributed documents, and posted YouTube videos. But if thorium’s second life on the Internet has grown the flock of adherents exponentially, it’s also pulled in more than a few people whose nuclear expertise doesn’t extend far past Wikipedia, adding a sheen of hype to the proceedings.

Still, the idea has legs, if new research programs by India and China are any indication. The former has just announced a prototype thorium-based advanced heavy water reactor, while the latter is researching a liquid fuel reactor based on the 1960s design. In the U.S., the race is being advanced not by the government but by some of the central movers and shakers of the Internet movement.

One of them, Kirk Sorensen, left his engineering job to study nuclear physics and start a company devoted to building small, modular liquid fluoride thorium reactors. The goal now may be to build some for the military, a tactic that would circumvent many of the challenges of building commercial reactors in the U.S. We met Kirk at the Thorium Energy Alliance summit in Washington, as well as an Army colonel focused on energy, and the head of the alliance, the thorium advocate and industrial engineer John Kutsch. We also interviewed Alexis Madrigal, senior editor at the Atlantic and author of Powering the Dream, a history of green technology evangelism, David Biello, associate editor at Scientific American, and Phillip Musegaas, the director of Riverkeeper’s Hudson River Program, which keeps careful tabs on the Indian Point Power Station, one of the country’s many aging nuclear plants, located about 30 miles from New York City. The nuclear physicist Alvin Weinberg, who led the first thorium reactor experiment, makes a cameo as well.  More at MotherBoard.