Their menace is that of "the uncanny"--of objects that make us nervous because they are strange and discomfiting and, more significantly, because they penetrate through the comfortable boundaries we maintain between life and death. Mannequins that move, views of our own innards--such things arouse a primal anxiety as they cross a line we sense ought not to be crossed. Nuclear energy arouses the same nervousness, breaking things we primally feel should remain whole and animating that which ought to be inert. With our first association with nuclear power being grotesque mass death, it is no wonder our fears about it are difficult to quell, even when its current widespread use is peaceful and extremely low in harm relative to other widely used energy sources.
Nuclear energy readily makes up the stuff of what Freud called obsessional thoughts, which are "correct as regards to affect and category but false owing to chronological displacement and substitution by analogy" (Draft K). The feelings and concerns we have about nuclear energy are perfectly correct, but they are quite plausibly displaced from their proper object--from death itself. Ultimately each of us will face a death that will mercilessly dissolve and scramble our own atoms, but one that in great likelihood will not be caused by nuclear power. Yet how easy it is to project our uncertain and future doom onto these opaque monoliths looming on our present horizons.
Websites such as enenews.com play on such displaced anxieties, recounting in their headlines unfamiliar elements, in Huge spike in cesium outside Fukushima long after 3/11 (which acutely exaggerates the study it cites), and incomprehensible events, as in Man dies at U.S. nuclear plant during incident with inflatable castle (?). A little research into enenews.com suggests that, though its provenance is as mysterious as the incidents it covers, its readers consider it a source of essential information that the mainstream media deliberately conceals from them, much as the readers of Alex Jones's Infowars do.
All of this matter might remain a PR problem for the nuclear sector if humanity did not need all the means it had available to avert steeply rising C02 emissions, which are now rising even faster amidst the current rage for decommissioning nuclear plants.