So there is a huge, incredibly consequential divide on climate policy. Not only is there a vast gap between the parties and their candidates, but this gap arguably matters more for the future than any of their other disagreements. So why don’t we hear more about it?

I’m not saying that there has been no reporting on the partisan climate divide, but there has been nothing like, say, the drumbeat of stories about Mrs. Clinton’s email server. And it’s really stunning that in the three nationally televised forums we’ve had so far — the “commander in chief” forum involving Mrs. Clinton and Mr. Trump, the first presidential debate and the vice-presidential debate — the moderators have asked not a single question about climate.

This was especially striking in Tuesday’s debate.

Somehow Elaine Quijano, the moderator, found time for not one but two questions inspired by the Committee for a Responsible Federal Budget — an organization concerned that despite relatively low budget deficits now and extremely low borrowing costs, the federal government may face fiscal problems a couple of decades down the line. There may be something to this, although not as much as deficit scolds claim (and Ms. Quijano managed to suggest that Mrs. Clinton’s proposals, which are fully paid for, are no better than Mr. Trump’s multitrillion-dollar debt blowout).

But if we’re worried about the longer-term implications of current policies, the buildup of greenhouse gases is a much bigger deal than the accumulation of low-interest debt. It’s bizarre to talk about the latter but not the former.

And this blind spot matters a lot. Polling suggests that millennial voters, in particular, care a lot about environmental protection and renewable energy. But it also suggests that more than 40 percent of young voters believe that there is no difference between the candidates on these issues.

Yes, I know, people should be paying more attention — but this nonetheless tells us how easy it is for voters who rely on TV news or don’t read stories deep inside the paper to miss what should be a central issue in this campaign.