The ambitious deal to curb climate emissions that the U.S. has reached with China could move us in the direction of fulfilling a long-sought dream of the environmental movement: Making the fate of the Earth just a tiny bit more relevant in electoral politics. It could help ensure that climate change becomes an issue — not a defining one, but one that matters more than it has historically — in the 2016 presidential race.

The deal — in which the U.S. has pledged to escalate reduction of emissions to 26 or 28 percent by 2025, and China has vowed to cap emissions and boost non-fossil fuels to one-fifth of energy sources by 2030 — is already being panned by Republicans. This is hardly surprising: They just won a big election in part by campaigning against President Obama’s alleged “war on coal.” But the new agreement between the U.S. and China — which together produce 45 percent of greenhouse gas emissions — could shift the politics of climate change in interesting ways.

As Brad Plumer explains, a key unknown is whether the U.S. can make good on its goals. This will turn on implementation of the Environmental Protection Agency’s proposed new rules to reduce emissions from existing power plants, and it will require more than that. Mitch McConnell has already vowed that the new GOP majority will fight any such efforts. That could complicate the U.S.’s ability to meet its end of any climate bargain.

This means GOP efforts to block Obama’s climate actions could suddenly take on vast practical implications and result in tangible international consequences. As Jonathan Chait details, Republican politicians have long justified opposing specific policies to curb our carbon emissions by claiming it won’t do any overall good, because China won’t do its part, too. Presuming this deal holds and China honors its end of it — which is uncertain — that excuse has just gone “poof.”

This is why Republicans such as McConnell are suggesting the deal “requires China to do nothing at all for 16 years,” and others are dismissing it as “non-binding” and a “charade.” If these things are true, then even those who are trying to come across as semi-open to accepting science, such as likely presidential contender Marco Rubio, can more easily argue there is still no need to do anything.  (See Chait’s response to those arguments here.)

Obviously it remains unknown whether GOP lawmakers will pay any near-term political price for opposing action on climate. But the timing of what’s coming on the international stage could dovetail with the presidential campaign calendar, forcing the issue on to the national agenda.

The deal with China is a key first step in the run-up to a global climate accord that Obama will try to negotiate in Paris next year. This will happen as the GOP presidential primary is gearing up, and its contenders probably will vociferously oppose any American participation in any such treaty, to appeal to GOP primary voters. What’s more, Obama is clearly undertaking a bid to make climate a major piece of his legacy, which could include more executive actions, further necessitating loud opposition to climate action from GOP presidential hopefuls.

Beyond that, any such treaty could become an issue in the 2016 general election, increasing the stakes around the question of whether — and how — we will go about sufficiently reducing our carbon emissions. “The question for all 2016 presidential candidates will be, Do you support the United States participating in a binding world agreement to address the climate crisis?” says Tiernan Sittenfeld, a senior vice president at the League of Conservation Voters.

Efforts to make climate an issue in the 2014 elections fell flat, leading to a lot of joyous mockery from certain segments of the press corps. But the 2016 map and electorate will be very different from those of 2014. Democrats will be relying more on millennials and socially liberal college educated whites who care about the issue or at least see it as a proof point in a broader contrast between the two parties’ ideological casts and visions for the future. I’m not saying the issue will prove all that important politically. But the deal with China raises the possibility that the fate of the planet just might take on a bit more political relevance than it has in the past.