Like every country involved in the Paris climate accord, America has pledged specific reductions in its carbon emissions. In addition to its existing goal — 17 percent reductions from 2005 levels by 2020 — the US also pledged to reach 26 to 28 percent reductions by 2025.

Even if Hillary Clinton had been elected, those targets would have been a challenge. Now that Donald Trump is in office, with an administration rolling back every climate regulation it can get its hands on and withdrawal from the agreement seeming likely, success is even more remote.

But how remote? Just how much will Trump affect the trajectory of US emissions?

Every year since 2014, the analysts at Rhodium Group (RHG) have issued a short report tracking US emissions progress to date and projecting emissions out to 2030, attempting to show how policy developments affect the trajectory.

Suffice to say, a great deal has changed since May 2016. (By some estimates, it’s been eleventy million years since then.) Back in March, RHG issued a quickie update, guesstimating the effect of rolling back Obama policies (Brad Plumer wrote about it for Vox.)

Now it has released Taking Stock 2017, with a more thorough review of Trump’s influence to date. Here’s what’s included:

For this assessment, we assume all recently finalized policies not explicitly rolled back by [Trump’s Executive Order] remain intact, including the 2017-2025 corporate average fuel economy (CAFE) standards, oil and gas methane standards for new sources and existing sources on public lands, and phasedown of hydrofluorocarbons (HFCs) under the Kigali amendment to the Montreal Protocol. With EPA’s Clean Power Plan (CPP) effectively on indefinite hold, we exclude it altogether. We also do not include potential Trump administration policies that were discussed on the campaign but have yet to be put into effect, including potential expansion of offshore oil and gas production.

This is an accurate reflection of what’s happened so far. But Trump is definitely going after CAFE standards. He’s definitely going after methane rules. His enforcement of the Kigali Amendment is very much in question. He may pull the US out of the Paris agreement. And he definitely wants to expand offshore drilling.

All of that means that RHG’s projection next year could look quite different, and grimmer, than this year’s.

That said, where are we headed given what Trump has done so far? Here’s the money graph:

The blue shading represents uncertainties in the forecast. The dark blue uncertainty is around “LULUCF,” the elegant acronym for land use, land use change, and forests. Energy market uncertainty has to do with the price of oil, natural gas, and renewable energy. Economic uncertainty has to do with the overall rate of economic growth.

As you can see, there’s enough momentum built up — from cheap natural gas, federal renewable energy tax credits, fuel economy improvements, and various state and city policies — to hit the 2020 target (if not necessarily by 2020).

But after that, it’s a plateau. With the current policy regime, it will be impossible to hit the 2025 target. And the policy regime is likely to get worse before it gets better.

RHG concludes with the greatest uncertainty of all:

Finally, the US’s ability to meet its 2025 Paris commitment will depend in large part on the outcome of the 2020 Presidential election. A change in the White House could bring about the same level of federal policy whiplash the country has just experienced, but in the opposite direction, and with enough time to make a meaningful dent in US emissions by the time the Paris commitment comes due.

A new president could make a “meaningful dent,” but the sad truth is that Trump’s flailing nihilism is almost certainly going to make it impossible for the US to keep its promises to the world.