Well, what do you know: President Obama can say the C-word after all. “Climate change is not a hoax,” he said in his acceptance speech at the Democratic National Convention. “More droughts and floods and wildfires are not a joke. They are a threat to our children’s future.”

The president was obviously drawing a contrast with Mitt Romney, whose speech at the Republican National Convention mocked the very idea of caring about climate change. “President Obama promised to begin to slow the rise of the oceans,” the Republican nominee said as the party faithful chortled. “And to heal the planet,” Romney added to further laughter. “My promise is to help you and your family.” Two days later, in the battleground state of Ohio, Romney repeated the line. Even George W. Bush, for all his resistance to tackling climate change, never made fun of it.

“It is nothing short of terrifying to imagine a party that openly mocks climate change taking back the White House,” the Obama campaign fired back via e-mail. True enough. But the president’s reticence has not been terribly reassuring either. Aside from his acceptance speech and three much briefer mentions in speeches to university audiences in Virginia, Colorado and Iowa the week before, Obama appears to have publicly brought up climate change only once in 2012, in an interview with Rolling Stone in April. The president has preferred to talk about “clean energy,” usually in the context of advocating an “all of the above” energy strategy: exploiting all available sources, including oil, gas and what he (inaccurately) calls “clean coal.”

The United States has been suffering through one of the hottest summers and worst droughts in its history, while the Arctic ice cap melted to its lowest level on record. Talk about terrifying. When white ice is replaced by dark seawater, more of the sun’s heat is absorbed rather than reflected, accelerating global warming. The loss of Arctic ice is the “equivalent of about twenty years of additional CO2 being added by man,” Peter Wadhams, a Cambridge professor of ocean physics, told the BBC.

Yet Obama remained silent. Even as his own administration’s scientists were affirming climate change’s role in causing the extreme weather events of 2012, the president declined to use his bully pulpit to make the connection clear to the public, much less attempt to rally Americans to action.

Of course, Obama has had a lot on his plate, above all a sluggish economy and high unemployment. But nothing else will matter if the planet becomes uninhabitable. If current emission trends continue, global temperatures will increase by nearly eleven degrees Fahrenheit by 2100, warns the International Energy Agency. “Even schoolchildren know this will have catastrophic implications,” said the IEA’s chief economist, Fatih Birol. Obama must know this, too; certainly his science advisers do. Perhaps that’s why he chose to utter the C-word again in Charlotte.

But there is much further to go, and the good news is that the political terrain for the climate debate may be shifting. The conventional wisdom has assumed that talking about climate change turns voters off, but a growing body of evidence indicates that speaking out about climate change—and above all how to fight it—can be a winner, thanks in part to the hellish summer of 2012. “I think we have achieved a real tipping point with the public, in that they finally see for themselves what the reality of climate change means,” says Joe Romm, editor of the nation’s leading climate science blog, Climate Progress, and author of Language Intelligence. Romm explains, “You can’t say one individual home run was due to steroids, but when somebody gets seventy in one season, then you understand what it means for them to be juiced. Our climate has been juiced by the steroids of greenhouse gases, which make almost every major extreme weather event more extreme.”

A new report called “Climate Solutions for a Stronger America” found that three in four Americans acknowledge that climate disruption is real; two-thirds believe action is required. Among the poll’s findings was that “a pro-climate action position wins votes among Democrats and Independents, and has little negative impact on Republican voters.” Such voters, the report suggests, will be receptive to framing the climate struggle as a classic quest narrative: heroes set off to vanquish villains in service of the common good. “Americans don’t run away from big challenges,” goes the script. “We turn them into big opportunities. We have a responsibility to our kids. But Big Oil and the Koch Brothers are standing in the way: corrupting our political process and blocking American clean energy innovation. It’s time to take our future back, and clean energy’s a great way to do it.”

In 2008, it looked as if Barack Obama would be the hero leading such a quest. His speech in Charlotte raised hopes among some environmentalists that after an extended absence, he may be ready to rejoin the battle. That would be a good thing. But if four years of Obama’s presidency demonstrate anything, it is the folly of waiting for him—or any president—to storm the barricades of entrenched power. If America is to vanquish the climate villains and win the quest for survival, we the people will have to be our own heroes.