OK, let’s be clear about one thing: Dolphins aren’t actually frolicking in the canals of a deserted Venice, a city on lockdown like the rest of Italy because of the global pandemic. But — as is sometimes the case — those misleading or faked viral tweets are an exaggerated version of something that is true, and also compelling: The shutdown of scores of tourist-packed gondolas has cleaned the murky waters of the ancient city to the point where fish are now visible.

And that’s not the only remarkable vision — practically a mirage, really — as the coronavirus crisis shutters the developed world’s economy to levels that resemble pre-Industrial Revolution society. From Beijing to Los Angeles, formerly slow-moving freeways are suddenly all but deserted at the height of rush hour, and the envelope of smog that once greeted those commuters has disappeared as well. Environmentalists have been posting pollution maps and satellite images of clearing skies that hearken to the 18th century.

Yet no one is really celebrating such a sudden drop in pollution on the eve of the 50th anniversary of the first Earth Day — not when the cause is a global pandemic that has already taken the lives of more than 500 Americans and at least 17,000 worldwide, with efforts to stem the coronavirus bring about an economic shutdown that may already be causing the biggest disruption since the Great Depression.

But on the front lines where scientists and activists have been fighting another planetary threat now abruptly pushed to a back burner — climate change — both the stunning images of blue skies, and gigantic scope of the political and societal interventions to stop coronavirus, raise some inevitable questions. Another world looks possible — but is it all a grand and temporary illusion, to be blurred by a return to normalcy once the all-clear whistle sounds?

In other words, will the fierce urgency of now created by the coronavirus — with the likelihood of massive government spending but also talk of significant changes in how to support a social safety net and regulate modern capitalism — create a template for next fighting the slower-moving public health crisis of climate change? Or will the economic lesson from the pandemic — with President Trump itching to defy his medical experts and proclaim America re-opened for business — instead be a craving for even less-fettered capitalism. If some leaders are willing to sacrifice Grandma to prevent a slowdown, what chance does clean air have?

I reached out to one of the smartest people I know — the Penn State University climate scientist Michael Mann, whose groundbreaking research led to the so-called “hockey stick graph” of Earth’s rising temperatures and who remains an outspoken voice for climate action. He responded to my email from an airport in wildfire-ravaged Australia, where the coronavirus forced him to cut short a lengthy speaking tour on the warming planet.

“On the one hand, this crisis accidentally demonstrates how our ongoing depletion of resources is threatening our planetary environment by providing us at least a fleeting window into what things might look like were we living more sustainability and demanding less from this planet,” he responded.

“And as we gradually see the sorts of services and conveniences we’re so used to begin to disappear and get a sense of how fragile our societal infrastructure really is—infrastructure that we now rely upon to support a population of 7.8 billion and growing people that are demanding more food, more fresh water, more space—we are starting to get a sense of how precarious modern civilization really is. We’re only one crisis away from dystopia. That crisis could be climate change if we don’t act now.”

It’s also worth noting that Mann is a frequent target of scorn among the climate-denialist right wing, and the seriousness of the coronavirus crisis also raises hope that American society might just be ready again to treat scientific expertise like his with greater respect.

But there are, of course, several other hands, beyond the obvious fact that few but the most apocalyptic-minded expect the emptiness of Venice’s canals or the Schuylkill Expressway to last forever. For one thing, both the economic slowdown and some complicated, loosely related geopolitics have caused oil prices to plunge to historic lows — which typically means Americans buying bigger gas guzzlers whenever car buying resumes (especially since the more well-off may also avoid mass transit, due to lingering virus fears).

Some experts note that cash-strapped corporations — including some that pledged to become carbon-neutral near the end of the late 2010s economic boom — are now likely to scuttle climate-related capital spending.

“Economics trumps environment in politics,” Rob Jackson, Stanford University earth scientist and chair of the Global Carbon Project, told me. He said he remains optimistic about the climate fight but also warned that “if the virus makes us more insular and protectionist, an international consensus to fight global warming may be harder to reach.”

The irony, of course, is that the coronavirus crisis and its lockdowns have also made it harder for the young activists most determined to radically change climate policy to protest any corporate or governmental backsliding. For example, a massive climate protest and strike planned for the 50th anniversary of the first Earth Day, on April 22, has now become online and digital — with its likely impact unknown.

But with events moving so quickly, the short-term course of the climate battle may already be determined by then. In the United States, what happens with a $2-trillion-plus coronavirus-related stimulus package — vehemently being fought over on Capitol Hill as I write this Tuesday morning — will likely show whether the pilots of progressive change or the captains of reactionary capitalism are steering this electric bus.

On one side, reform-minded Democrats are essentially arguing that bailing out American big business demands green-minded environmental change as one of the conditions of that relief. The version of the massive stimulus package as drafted by House Democrats offers a significant bailout for the renewable energy sector that includes wind and solar power, and even proposes cuts in pollution in return for the $50 billion chunk sought by the nation’s airlines.

Not surprisingly, Republicans and their zealously pro-corporate leader on Capitol Hill, Senate Majority Leader Mitch McConnell, see the notion of saving the planet as something they’re most comfortable with decrying as “social engineering” or “a liberal wish list.” They are eager to race toward the familiar smoggy skies of business as usual — laughing at airline pollution controls even as they consider the American Petroleum Institute’s request to relieve Big Oil from regulations, which sure sounds like reverse social engineering to me.

The importance of this moment can’t be understated, because in a society that’s been hopelessly politically gridlocked for at least a decade, this moment of crisis — horrible as it is — is also probably our only real chance at changing the course of this otherwise doomed battleship. We should be imploring our leaders, especially the ones currently quarreling in the corridors of Congress, to ponder the bigger meaning of America’s short-sighted vision in preparing for this pandemic — eliminating key positions and poo-pooing science in general.

Do we really want to be here again in 10 or 20 years — or less — over rising sea levels, drought, floods or wildfires ... or deeper fallouts like famine, mass migration or war? Or can we make sure that, in stimulating the suddenly moribund U.S. economy, that we stimulate it away from dirty fossil fuels and towards clean energy?

Lawmakers should take a deep breath of the spring air along the Potomac — for one shining moment not tainted by thousands of tailpipes up on the Capitol Beltway — and ponder all the energy and human ingenuity that’s being thrown at the coronavirus, and imagine doing that next for climate change. A better world is possible. You can feel it in the air.