For anyone with an interest in ensuring our planet remains livable, the news of late could not be more dire. Scott Pruitt, the head of the Environmental Protection Agency, questions the right of the EPA to regulate greenhouse gas emissions! CPAC conservatives hold a panel on “fake climate news!” President Donald Trump’s proposed budget will axe “tens of billions of dollars” from the EPA’s budget! And in a pending executive order that will nix most Obama-era carbon regulations, the only thing that kept the 2015 Paris Climate Agreement off the list was reportedly the whim of Jared Kushner and Ivanka Trump.

Meanwhile, in the Antarctic, a record-size crack is growing in the continent’s fourth-largest ice sheet. In California, people are enduring record floods, and in New York City, we’re wearing shorts in February. Fresh off of 2016, yet another hottest year on record, Americans are worrying about climate change in record numbers.

To tackle the problem, we need an immediate, massive globalized mobilization on the order of World War II. Instead, we’ve got Trump, who has called climate change a “hoax,” begun dismantling environmental protections against dirty coal, and installed cabinet heads whose “meh” stance on climate science is a new form of denial. The timing of Trump’s election, just days after the Paris Climate Agreement entered into force, is both tragic and absurd. Trump, after all, campaigned on a promise to “cancel” the accord. It has prompted an urgent question: Over the next four to eight years, can the world meet its greenhouse gas–cutting goals without—or despite—the U.S. federal government?

This is a complex and speculative question. But it is one worth exploring, if only to avert apocalyptic levels of despair. Because even a brief exploration suggests that all is not lost—at least, not yet.

First, the bad news: If all countries walk backwards down the Trumpian path, we’re in for big trouble. Today, atmospheric carbon dioxide concentrations are higher than they have been in 800,000 years, and well above what is considered a safe threshold. The resulting global warming will cause more sea level rise, ocean acidification, drought, and mass extinction, and so much armed human conflict that the Pentagon has declared climate change “a significant risk to U.S. national and international security.”