Climate change is one of the most critical issues facing humanity for, oh, the next 10,000 years, but we’ve barely heard about it in this presidential campaign. So let’s quickly recap the difference between Trump and Clinton on global warming. Because it’s really quite simple — and stark.

Clinton: Hillary Clinton wants to use various regulatory levers at the president’s disposal to nudge down US greenhouse gas emissions bit by bit. Tighten fuel-efficiency standards for vehicles here; plug methane leaks from natural gas infrastructure there. Defend President Obama’s Clean Power Plan to reduce CO2 from coal plants. Bolster appliance standards and building codes. Each individual regulation is penny-ante stuff, but it piles up. The aim is to ratchet down overall US emissions 26 to 28 percent below 2005 levels by 2025:

If you compare this with the vast scale of what’s needed to halt global warming — an 80 percent cut by 2050 that involves completely retooling our electricity, transport, industrial, and agricultural sectors — Clinton’s proposals are laughably, tragically inadequate. But they’re also at the outer edge of what a president can do without buy-in from Congress.* You can’t get a carbon tax without Congress. Or a nationwide clean energy standard. Or any of the ambitious regulations California is now tinkering with.

So Clinton is basically gambling that this will do for now. Use regulations to slowly grind emissions down. Work with countries like China and India to grind their emissions down under the Paris climate deal. And hope for big political or technological shifts down the road that enable even bigger cuts. This was basically Obama’s plan. It’s far from a solution. It’s easy to imagine it failing. But it’s a plan, at least.**

Trump: Trump’s climate plan is even simpler: He doesn’t have one. Doesn’t seem to care. Never talks about the issue, save for calling global warming a Chinese hoax. He’s said that he’d refuse to meet US obligations under the Paris climate deal (and, since it’s non-binding, he could do that). He’d undo various CO2 regulations that Obama has put in place, like the Clean Power Plan (yes, he could do that too). He’d push to allow more oil and natural gas drilling on public lands. It is very easy to imagine emissions rising under Trump and nearly impossible to imagine them falling sharply.

So that’s the choice in this election. Clinton wants to keep chipping away at this enormous boulder of a climate problem, all in the hopes that bigger cracks eventually appear. Trump says the boulder’s fine as is — if anything, it could stand to be even bigger.

It may not be the world’s most inspiring choice, but it’s certainly a stark one.

Footnotes

* There is one other drastic executive action that Clinton could conceivably take that she never mentions. Under Section 115 of the Clean Air Act, a president could conceivably cite the Paris climate deal in order to enact a nationwide cap-and-trade program without Congress. But it’s unclear if the courts would uphold this — she’d be wandering into wildly unprecedented legal territory.

** Again, Clinton’s plan assumes that Congress is at least partly controlled by Republicans who refuse to do anything on climate change. If, by contrast, Trump loses in a landslide and Democrats take back both the Senate and the House, then we’re in a different world — and Clinton hasn’t really given a good indication of what she’d push for. This would be an excellent question to ask at the third presidential debate!

(Also note that this was one key difference between Clinton and Bernie Sanders in the primary. Sanders would probably behave pretty similarly to Clinton as president if faced with a recalcitrant Congress. But Sanders also gave an indication of the more sweeping things he’d push for if he had congressional support: an economy-wide carbon tax or a nationwide fracking ban or massive investments in renewable energy. Clinton, by contrast, has stayed quiet about that prospect.)