The psychological toll, however, was immense. Even before the accident, America’s romance with nuclear power had begun to chill. Three Mile Island sent it into the deep freeze. Many years passed before the Nuclear Regulatory Commission got a chance to review an application to build a new power plant. The devastating 1986 Chernobyl nightmare in Ukraine, the worst catastrophe at a nuclear power plant, hardly reassured wary people, even those willing to chalk up that horror to useless Soviet engineering and management. Now we have the continuing ordeal of the Fukushima Daiichi plant in northeastern Japan, crippled by a 2011 earthquake and tsunami. Small wonder that strong antinuclear sentiments are expressed, like those in Mother Jones on the heels of the tsunami, to the effect that “replacing coal and oil with nuclear power is like trading heroin for crack — different addictions, but no less unhealthy or risky.”

Yet American attitudes on nuclear power, as measured by opinion polls, are far from irrevocably negative. As TMI faded in collective memory, the popularity of that energy source has waxed and waned, each rise tempered by a new cause for alarm, notably Chernobyl and Fukushima. Many power plants that had been on the drawing boards before 1979 were built. In the last few years, new ones have been proposed, encouraged by President Obama, who has described nuclear energy as necessary — along with renewable sources like wind and solar — in any plan to wean the country from fossil fuels. The need for swift action would seem greater than ever, given new warnings from a United Nations panel that time is running short for countries to adopt strategies to keep worldwide carbon emissions from reaching intolerable levels.

It is hard to grasp how American reliance on nuclear energy could disappear soon, if ever. According to the World Nuclear Association, a London-based group that promotes nuclear power, there are 104 nuclear reactors in the United States. They accounted in 2011 for 19 percent of this country’s total electricity output. While that is half of what coal-fired power plants generated, and roughly 60 percent of that produced by plants relying on natural gas, it is still a lot. Projections suggest that America’s energy needs will only keep growing.

Still, nuclear power scares the pants off people unlike any other energy form. The phenomenon is hardly new. Baby boomers grew up with a stream of 1950s horror movies like “Godzilla” and “The Amazing Colossal Man,” premised on radiation’s monstrous consequences. Fast forward to Chernobyl, whose psychological impact was reflected in a 2005 study conducted under the aegis of several international groups, including the International Atomic Energy Agency. This review concluded that “the mental health impact of Chernobyl is the largest public health problem unleashed by the accident to date.” A year after Fukushima, Spencer Weart, a physicist and science historian, wrote for this newspaper’s Dot Earth blog that nuclear fear retained “its status as the supreme horror,” a psychological malaise that “does not accompany other materials that put people at risk of cancer and other deadly illness.”

Could the events at Three Mile Island happen again? Not very likely, at least not at Three Mile Island itself. TMI-2 was permanently shut down, and TMI-1, the first reactor there, would seem not long for this world; it is expected to be decommissioned, a process that was supposed to begin this year but has been delayed until 2034.

But is that enough to allay all nuclear fears in this country? Many TMI-era reactors are still around. So it is perhaps not TMI, the modern TMI, to suggest that the probable answer is no.

CLYDE HABERMAN, a regular contributor to Retro Report, has been a reporter, columnist and editorial writer for The New York Times, where he spent nearly 13 years based in Tokyo, Rome and Jerusalem. Subscribe to our newsletter here and follow us on Twitter @RetroReport.

This article first appeared in The New York Times.