Bloomberg: Some environmentalists are thrilled over Tuesdays announcement of the planned closing of Californias Diablo Canyon nuclear power plant. They might want to reconsider: Fighting climate change requires more nuclear power, not less. That Diablo Canyons two reactors could be allowed to shut down is alarming evidence that too little effort is being made to reduce greenhouse-gas emissions. The electricity that the Diablo Canyon plant generates, which amounts to about 9 percent of Californias power,...