Earlier this month, Syria signed the Paris Climate Agreement, leaving the U.S. the only country that has rejected the U.N.’s global pact to fight climate change. 

Meanwhile, a new study from Yale shows that seven in 10 Americans believe that global warming is happening.

So why doesn’t the federal government reflect the will of the majority? Is it too late to depend on our political leaders to make real changes when it comes to environmental change?

According to historian Nancy Koehn, the leaders to turn to might not be federal — they are represented at the U.N. climate talks by state and local governments, corporations and private companies with a vested interest in improving the country’s impact on the planet. “They are on it,” Koehn told Boston Public Radio Tuesday. “They have state incentives in place, they have carbon pricing in place, they have hosts of examples of companies, from Disney to General Motors to Shell.”

The incentives aren’t necessarily moral, particularly for huge energy corporations, but based on an economic benefit, Koehn says.

“If you collected the business, the economics of trying to reduce carbon emissions by the pledge, you would create the world’s largest economy behind China and the United States,” she said. “In other words, when lots and lots of politicians talk, including Al Gore, about the economic opportunities of global climate change in terms of jobs and new industries and existing industries, they are not blowing smoke — they are talking about something real.”

Harvard historian Nancy Koehn holds the James E. Robison Chair of Business Administration at Harvard Business School. Her new book is "Forged in Crisis: The Power of Courageous Leadership in Turbulent Times." To hear her full interview with Boston Public Radio, click on the audio player above.