Over at the New Yorker, Elizabeth Kolbert laments the fact that neither President Obama nor Mitt Romney had anything to say about climate change during the second presidential debate Tuesday. Oh, sure, they talked about energy — about oil leases, about coal, a few quick nods toward renewable energy. But nothing about this warming planet of ours. Nothing about the summer's droughts or wildfires or the rapidly melting Arctic.

Not a hot topic. (AP)

So I was curious to look back at how Obama and John McCain talked about this issue in the previous election. The tone was strikingly different. During the town hall debate in 2008, an undecided voter in Nashville asked the two candidates: "[W]e saw that Congress moved pretty fast in the face of an economic crisis. I want to know what you would do within the first two years to make sure that Congress moves fast as far as environmental issues, like climate change and green jobs?"

McCain agreed that climate change was a critical issue, even in the face of a struggling economy:

Look, we are in tough economic times; we all know that. ... But when we can -- when we have an issue that we may hand our children and our grandchildren a damaged planet, I have disagreed strongly with the Bush administration on this issue. 

Now, how -- what's -- what's the best way of fixing it? Nuclear power. ... Nuclear power is safe, and it's clean, and it creates hundreds of thousands of jobs. We can move forward, and clean up our climate, and develop green technologies, and alternate -- alternative energies for -- for hybrid, for hydrogen, for battery-powered cars, so that we can clean up our environment and at the same time get our economy going by creating millions of jobs.

Obama wholeheartedly agreed—he just thought McCain was placing too heavy an emphasis on drilling for fossil fuels:

This is one of the biggest challenges of our times. And it is absolutely critical that we understand this is not just a challenge, it's an opportunity, because if we create a new energy economy, we can create five million new jobs, easily, here in the United States. It can be an engine that drives us into the future the same way the computer was the engine for economic growth over the last couple of decades. ... 

One last point I want to make on energy. Sen. McCain talks a lot about drilling, and that's important, but we have three percent of the world's oil reserves and we use 25 percent of the world's oil. So what that means is that we can't simply drill our way out of the problem. And we're not going to be able to deal with the climate crisis if our only solution is to use more fossil fuels that create global warming.

Notice, in particular, Obama's main criticism of Republican policy back in 2008 was that "we can't simply drill our way out of the problem."

Jump ahead to the 2012 town hall debate, and the candidates were asked about gas prices. Instead of conceding that there's just not much the president can do to affect the price of gasoline, Obama spent his time talking about the boom in oil and natural gas extraction under his watch. There was then a fair bit of bickering with Romney over whether oil drilling on federal lands was up or down. (The answer is complicated, but in truth, the recent boom in oil production has fairly little to do with Obama's policies either way.) Even as the candidates danced around topics like renewable energy, climate never came up.

Perhaps that's because no one asked the candidates directly about global warming—after the debates, moderator Candy Crowley said she had a question ready to go "for all of you climate change people," but there wasn't enough time. Though it's also true that back in 2008 there were two candidates eager to talk about the subject, and in 2012 there are two candidates eager to talk about anything but.