He said that secondary effects of major earthquakes have not received adequate attention, pointing to the vast industrial complexes of oil refineries, chemical plants and nuclear facilities that dot the West Coast of the U.S.
Nuclear energy advocates defended the overall safety of nuclear plants and voiced confidence that the situation in Japan wouldn't stop the push for new plants in the U.S. "It's way, way, way too early to be drawing policy conclusions from it," said Keeley, the Nuclear Energy Institute spokesman.
There are 442 nuclear reactors around the globe, which supply about 15% of the world's electricity, according to the London-based World Nuclear Assn. Plans are underway to build more than 155 additional reactors, mostly in Asia, with 65 currently under construction, the association said.
With nearly a quarter of the existing reactors, the U.S. is the world's largest producer of nuclear power, accounting for more than 30% of nuclear generation of electricity.
But the U.S. plants now operating were started before the Three Mile Island accident in 1979, in which a reactor near Harrisburg, Pa., suffered a partial meltdown that resulted in limited radiation release.
One thing that should be kept in mind is that Japan's Fukushima No. 1 plant, where the biggest problems have been unfolding, is 40 years old, said James Acton, a nuclear expert with the Carnegie Endowment for International Peace.
"The industry will argue that modern reactors have safety features that could have prevented Fukushima," said Acton, a physicist and nuclear power supporter. "I strongly suspect that claim is correct. I also think it is going to be amazingly difficult to sell that argument to the public."
Times staff writers Thomas H. Maugh II and Ralph Vartabedian in Los Angeles contributed to this report.