A leading Republican presidential candidate once said:

“Instead of idly debating the precise extent of global warming or the precise timeline of global warming, we need to deal with the central facts of rising temperatures, rising waters and all the endless troubles that global warming will bring.”

Speaking at a wind power plant in Oregon, the lifelong conservative promised to, if elected, “not shirk the mantle of leadership that the United States bears” to act on climate.

The candidate’s rationale was simple: “We stand warned by serious and credible scientists across the world that time is short and the dangers are great.”

That was back in 2008, and the candidate was, you guessed it, Senator John McCain. In typical maverick fashion, McCain’s practical views on climate change diverged greatly from many of his GOP peers. He was the only serious Republican presidential candidate to call for mandatory limits on greenhouse gas emissions. While his plan was to cut emissions only 60 percent below 1990 levels by 2050, when the leading Democratic candidates’ proposal was to cut them by 80 percent over the same period, it still was a plan to address climate change.

I began writing this blog post several weeks ago — without knowing McCain was in his final days. That’s because it’s tough to talk about the politicization of climate change in the United States without reflecting on what might have been had he been successful in his 2008 bid for the presidency.

Climate change is a story. A true story. But a story nonetheless. And, like all narratives, it has a beginning, middle and end.

The story began at the turn of the 19th century during the Industrial Revolution when capitalism compelled our species to begin pumping carbon dioxide into the atmosphere in pursuit of profit. Since then, we’ve increased atmospheric carbon concentration by more than a third, according to NASA.

Then came the advent of consumerism during the mid-20th century, when we doubled down on our demands on the planet to provide us with all the luxuries we didn’t even know we wanted. It was around this time that we started to get wise about our global environmental impacts. Rachel Carson’s Silent Spring helped kick off the modern environmental movement. Our first forays into the stars gave us a glimpse of the fragility of this Blue Marble we call home. In 1970, Denis Hayes, who I had the privilege of interviewing a few years back for GreenBiz, organized the first Earth Day. More than a decade later in 1988, the World Meteorological Organization established the Intergovernmental Panel on Climate Change with the support of the United Nations Environmental Programme.

Now nearly two decades into the 21st century, our climate narrative remains uncertain. On the one hand, clean energy innovation continues to advance and the global community has come together to embrace the Paris Agreement on climate change. On the other hand, extreme weather events connected to climate change are devastating communities and economies around the globe, and the Trump Administration and other denialist forces with a monied interest in fossil fuel extraction continue to peddle reactive climate policies.

But this isn’t the end. The finale of our fate hasn’t been written. We still can influence the outcome of this narrative.