Donald Trump’s ascension to the presidency is a stunning blow to hopes for avoiding the worst impacts of global warming. But a broad-based, grassroots movement committed to cutting emissions and promoting clean energy must continue and intensify – the stakes are simply too high to give up.

One possibility is, we’ve lost. It’s a real possibility, and we should consider it carefully instead of ignoring it because it’s emotionally unpalatable. I think the argument would go like this: The idea that humans would move quickly enough off coal and oil and gas to salvage the planet’s climate was always a long shot. When I wrote the first book on all of this back in 1989, I interviewed a political scientist who said “it’s the problem from hell,” with so many interests at odds, and so much money invested in the status quo, that it was hard to see a real path forward. And that was back when we thought global warming would roll out somewhat slowly — when we feared the consequences that would unfold in the second half of this century. The scientists, it turns out, had been much too conservative, and so “ahead of schedule” became the watchword for everything from polar melt to ocean acidification. Already, only 17 years into the millennium, the planet is profoundly changed: half the ice missing from the polar north, for instance, which in turn is shifting weather patterns around the globe. That galloping momentum of warming (building on itself, as white ice gives way to blue ocean and as fires in drought-stricken forests send clouds of carbon aloft) scares me. It should scare everyone; for a decade now it has threatened to take this crisis beyond the reach of politics. To catch up with the physics of climate change we’d need a truly stunning commitment to change, an all-out, planet-wide decision to push as hard as we’ve ever pushed to spread clean energy and shut down the dirty stuff.

Even if he doesn’t scrap the Paris accord, Trump and his team will do all they can to slow the momentum for action.

The closest we’ve gotten to that — and in truth, it wasn’t all that close — was the Paris Agreement that went into effect last November 4. It committed all the nations of the world to holding the planet’s temperature increase to as close to 1.5 degrees Celsius as possible, and by all means below 2 degrees. It lacked enforcement mechanisms and strict timetables, but it did at least signal the planet’s willingness to go to work. And it helped conjure up the counter-momentum that was beginning to take hold: renewable energy was suddenly outpacing fossil fuel in many places. Carbon emissions were starting to stabilize. Four days later, Donald J. Trump was elected. He has promised, of course, to scrap the Paris accords, but even if he doesn’t do that, he and his team will do all they can to slow that building momentum. And since pace is everything here, that might well be enough. Our not-very-good-in-any-event chance just got much much harder. But — and I say this with a certain weary sadness — the chances have not gotten so much harder that one can justify giving up. There definitely are days when I wish one could simply say ‘that’s that’ and walk away, and since I don’t live next to a refinery I suppose I have that luxury. Doing so would require, however, ignoring a few realities that shouldn’t be ignored. One is the almost unbelievable fall in the price of renewable energy, which is continuing apace. Each passing month brings cheaper solar panels, more efficient wind turbines, more powerful batteries at lower cost, shinier electric cars. The pieces are there, and in a few spots they’re actually being used: If Denmark can generate half its power from the wind, then so can lots of other places. If India can build the world’s largest solar farm in a matter of months, then there’s no reason others couldn’t follow. The engineering breakthroughs of the last decade have made rapid conversion technologically plausible; as Mark Jacobson and his Stanford team have demonstrated, you can make the numbers work — they’ve shown state-by-state that getting to 80 percent clean power in the U.S. by 2030 isn’t easy, but it is possible. The other reality is darker, but no less real: global warming will happen on a spectrum. It’s not like everything is okay up to 2 degrees, and then everything is hell. Hell is breaking loose now, and we’re barely past 1 degree. Two degrees will be exponentially tougher — but 3 degrees will be exponentially tougher than that. The battle never really ends: you just keep falling back to the next redoubt, finding some new weapon with which to fight, yielding no more ground than you must. We’re never going to reach the point where it can’t get any worse. It can get worse, and it will if we don’t battle. Where, then, will the battle be fought?

To some degree, in Washington. That’s been the center of the environmental fight these last eight years, with defeats (cap-and-trade) and victories (the Keystone XL pipeline) and constant, focused lobbying. In fact, we’ve lost at least as much as we’ve won: Even as we greet the Trump disaster, it’s important to account honestly for the Obama years, when America passed Russia and Saudi Arabia as the greatest oil and gas nation on earth. Yes, good organizing helped break the back of the coal industry, but that carbon-spewing anthracite was mostly replaced by methane-leaking fracked gas; depending on how you count the warming effect of that CH4, it’s entirely possible America’s greenhouse gas emissions went up during the Obama era. Still, D.C. was a place you could stand and fight: Obama had promised to do something about climate change, and you could try and hold him to that promise.

At least for now, there’s only defense to be played, but defense is half of any game.

Trump has promised just the opposite, and there’s no real leverage to hold over him. As his cabinet appointments have made entirely clear, he’s going to gut the EPA and turn the Department of Energy into a playground for the oil industry. (And who knows what he and Rex Tillerson and Vladimir Putin are cooking up for Russia.) At least for now, there’s only defense to be played, but defense is half of any game. If the filibuster remains in place and the Democrats can round up 40 votes, the worst damage can perhaps be avoided. That’s why we’ll muster and march: After the inauguration weekend’s Women’s March, a giant climate justice gathering on April 29 figures to be the next crucial date on the movement calendar. My guess, however, is that most of the action will be outside the Beltway in the next few years — that Sacramento and Albany will be capitals of almost equal significance as we struggle to keep the energy revolution going. California is the world’s sixth largest economy, and it has begun to prosper from a tide of clean energy investment; success there will help drive investment in the right direction. New York is halfway into the most ambitious utility restructuring plan on the continent. Assuming that Governor Andrew Cuomo stays the course (and as a pol with an eye on bigger things, that seems a reasonable bet), the Empire State will demonstrate what a modern energy system might look like. That won’t turn off the dirty power plants in the rest of the country — they’ve been granted a reprieve by Trump’s election — but it will keep Wall Street paying attention. And even across the middle of the country, sense keeps breaking out. Iowa is largely wind-powered now; even Ohio’s Republican governor, John Kasich, recently refused to scrap renewable energy targets. In this new landscape, the large, sprawling, diverse climate movement that has sprung up in the last decade can push the process in many useful ways.

Take, for instance, the ongoing battles against new fossil fuel infrastructure, exemplified in the last few years by the battles over the Keystone XL and Dakota Access pipelines. Those were crucial fights, and only in part because they slowed the construction of particular pipelines. They also scrambled the investment thinking of multinationals, banks, and investors. Canada’s tar sands, for instance, may have been dealt a fatal blow by the various pipeline battles — even if they’re eventually built, billions of dollars in new mining operations were deferred or canceled in the meantime. The idea that tar sands output would triple or quadruple has vanished; even Exxon is facing the likely need to write off its investment in the north. The battle waged at Standing Rock over the Dakota Access pipeline a particularly powerful chapter in this fight, and not just because it made crystal clear to the larger public what many of us have known for years: that frontline communities, and in particular Native Americans, are leading much of this struggle. Standing Rock also demonstrated that most of the nation’s (and many of the planet’s) big banks were still in the business of underwriting fossil fuel. That means new targets, and ones vulnerable to consumer pressure — the bank-lobby sit-ins that have taken place across the country are just the first wave, I’d wager. In fact, the fossil fuel divestment movement will see a new surge of organizing. It’s already enormous, the biggest campaign of its kind in history, with endowments and portfolios worth more than $5 trillion pulling out of some or all of the fossil fuel stocks. And it’s already done damage — as Peabody Coal went bankrupt, it explained to the SEC that damage from the divestment campaign was one big reason. Now it becomes an even more compelling place to act: with the system jammed in D.C., the pressure will inevitably build elsewhere. And increasingly, divestment campaigners are taking on iconic targets, places like the Nobel Foundation or the planet’s great museums, making the case that our culture simply can’t survive the coming meltdown. That’s crucial, because in the end the real fight is not over a pipeline or a windmill or even a carbon tax. The real fight — all real fights — are over the zeitgeist. They’re about who controls the vision of the future.

Even distracting presidential tweets can’t crowd out the brute actuality of drought and flood and heat.