Coal has long had a grip on American politics. That's why politicians worry about its fate. They tout the fossil fuel's contribution to the U.S. economy, but lately they've also been trying to find a way to clean up coal's image.President George W. Bush said in his 2008 State of the Union address, "Let us fund new technologies that can generate coal power while capturing carbon emissions" — emissions that contribute to global warming. That same year, candidate Barack Obama visited coal country in Virginia and said this about cleaner coal: "We figured out how to put a man on the moon in 10 years. You can't tell me we can't figure out how to burn coal that we mine right here in the United States of America and make it work. We can do that."And now President Trump is on board the coal train, saying recently: "My administration is putting an end to the war on coal. We're going to have clean coal, really clean coal."Right now, burning coal contributes more carbon dioxide to the atmosphere than any other industrial process. There is technology to strip the CO2 from coal and bury it or use it elsewhere, either before the coal is burned or after. The federal government spent 20 years and billions of dollars to make it work. The result: just two commercial power plants in the U.S., both heavily subsidized. One is the Petra Nova plant in Texas that Energy Secretary Rick Perry visited last week in a show of support. The other is in Mississippi and has yet to open officially.But two groups usually at odds with each other — environmentalists and coal companies — want "carbon capture" to succeed.David Hawkins of the Natural Resources Defense Council says it's just common sense. There are thousands of coal plants around the world. Many were recently built, and over a thousand more are planned. "How likely is it that governments are going to shut down a power plant that's only 10 years old that might have cost a billion and a half dollars or more to build?" he asks.Hawkins says it's likely that most of them will be running for decades. "And if they put all that carbon pollution into the atmosphere," he predicts, "it's inevitably going to bust the budget for a safe climate."That's also the conclusion of the Intergovernmental Panel on Climate Change, which advises the United Nations. The IPCC predicts that without carbon capture, the goal of keeping the planet from warming more than 2 degrees Celsius above pre-industrial levels won't be met. That goal was set at the Paris climate conference in December 2015.Several other environmental groups, such as the Environmental Defense Fund and the Clean Air Task Force, agree. And last February, some of them sent a letter to Congress pushing for tax breaks to help coal plants capture carbon. Their co-signers included heavyweights in the coal industry — Peabody Energy, Cloud Peak Energy and Arch Coal.From the industry's perspective, pollution controls, natural gas and renewables are killing coal.Richard Reavey of Cloud Peak Energy says "climate-friendly" is the future — like it or not. "You know, here's the deal," he says. "The time for discussing, debating the science of climate change is over. It is a political and social reality."Reavey says it's now a matter of choosing which technology to use to cut carbon emissions from coal before more coal jobs are lost. "And I don't think it is reasonable, appropriate, just or politically smart to say, 'We'll do that after we kill the coal industry,' " he says, along with tens of thousands of good jobs in that industry.There are still plenty of environmental groups that want to see coal disappear. Charles Cray at Greenpeace says carbon capture is a political tool. "It's been the technology that's been used to justify trying to prop the industry up for a while," he says.Cray argues that taxpayers' money should go for renewable energy rather than a technology to extend the life of fossil fuelsCarbon capture does add significant costs to a coal plant. Some costs can be recovered by selling CO2, which is used to pump up oil from hard-to-reach reservoirs. But large-scale use of carbon capture would require a network of pipelines to move captured CO2 to geologic burial sites.Nonetheless, this cooperative effort by environmental groups and coal companies has allies in Congress. Republicans have introduced a bill in the Senate to give carbon capture helpful tax breaks. The House of Representatives is taking up its own version. And Perry's visit to Petra Nova shows that some people in the pro-coal Trump administration are paying attention. Copyright 2017 NPR. To see more, visit http://www.npr.org/.