Duke Energy’s decision to dismantle a Florida nuclear power plant rather than undertake the costliest- ever U.S. atomic repair shows how rapidly cheap natural gas is remaking the U.S. power industry, hastening a shift from traditional fuels such as coal and uranium. Duke’s Crystal River Unit 3 plant in Florida joins Dominion Resources Inc.’s Kewaunee reactor in Wisconsin as the first to be shuttered in the U.S. because of growing shale gas supplies, serving as signposts for utilities from Japan to Belgium also considering decommissioning reactors. At least four other U.S. reactors are also at risk of early retirement due to new power market economics, said Julien Dumoulin-Smith, a New York City- based analyst with UBS Securities LLC, in a telephone interview.—French industrial groups are up in arms as their once-celebrated nuclear-energy edge evaporates. After decades when their factories churned out everything from steel, glass and chemicals with one of the cheapest power prices in Europe thanks to the country’s 58 nuclear reactors, French companies’ competitive advantage is being whittled away as the U.S. embrace of shale gas cuts energy prices there and as Germany gives businesses fiscal breaks against [green] electricity costs.