As President Joe Biden’s Special Presidential Envoy for Climate, John Kerry will play perhaps the most critical role internationally in managing a planetary crisis. To succeed, he’ll need to repair the diplomatic damage done by former President Donald Trump while steering through clashing interests at home: a defiant private sector on the one hand, and strident climate activists on the other. Kerry has the background for the job. Thirty years ago, he attended the first major United Nations conference on climate change in Rio de Janeiro, and witnessed the signing of the Kyoto Protocol in 1996. He led precedent-setting, though ultimately failed, climate legislation in the Senate in 2010. He was the first Secretary of State to visit Antarctica and in 2015 signed the Paris Climate Agreement on behalf of the U.S. Kerry has come out swinging as climate czar, blasting Trump for his “reckless behavior,” vowing to commit $2 billion to help developing nations pay for the effects of climate change and espousing a 1.5 degree Celsius limit on warming. I sat down with him in Washington last week right before he was sworn in to find out how he plans to accomplish his goals and what else he has on his agenda. Here’s a lightly edited transcript of our exchange.

Amanda Little:  Biden has pumped up his climate plan after early criticism from the left that it was too cautious. How will you balance the demands of progressives with the more moderate climate agenda of the Biden administration?

John Kerry:  President Biden asked me to chair his task force together with [New York Representative] Alexandria Ocasio-Cortez to bring people together to find common ground. Senator [Bernie] Sanders and his supporters have made great contributions to the conversation. They’re pushing because they understand the urgency, and I share that sense of urgency 100%. President Biden has a much stronger program as a consequence of everybody’s input from all corners. There’s no room for BS anymore — from anyone in the debate.