In 1979, there was a partial meltdown at a nuclear plant on Three Mile Island, in Dauphin County, Pennsylvania. I was a young newspaper editor at the time, and I was caught up in coverage of the resulting debate about whether nuclear power could ever be safe. I have long forgotten the details of that episode, except for one troubling thought that occurred to me in the middle of it: The experts we relied on to tell us whether a given design was safe, or indeed whether nuclear power generally was safe, were people with advanced degrees in nuclear engineering and experience running nuclear plants. That is, we were relying on people who made their living from nuclear power to tell us if nuclear power was safe. If they started saying out loud that anything about the nuclear enterprise was iffy, they risked putting themselves out of business.