After admitting "we don't know yet about the situation in Japan," Josh Marshall nevertheless defends nuclear energy. Saletan is on the same page:

Even if you count all the deaths plausibly related to Chernobyl9,000 to 33,000 over a 70-year periodthat number is dwarfed by the death rate from burning fossil fuels. The OECD's 2008 Environmental Outlook calculates that fine-particle outdoor air pollution caused nearly 1 million premature deaths in the year 2000, and 30 percent of this was energy-related. You'd need 500 Chernobyls to match that level of annual carnage. But outside Chernobyl, we've had zero fatal nuclear power accidents.

Yglesias echoes:

I don’t really want to be the nuclear apologist guy. I think of myself as a clean energy guy. I’m an energy efficiency guy. But what I’m definitely not is a fossil fuel guy. And you can’t make sense of the safety concerns around electricity generation unless you put the nuclear risks in some kind of context. 

I'm in favor of many, many more nuclear power plants as the only realistic way right now to get our carbon use down.