Pope Francis is addressing the United Nations in New York on Friday, September 25. In Thursday's address to a joint session of Congress, the pontiff denounced the death penalty, called for economic equality, and cited four historically meaningful Americans who dedicated their lives to some form of service: President Abraham Lincoln, Dr. Martin Luther King Jr., Dorothy Day, and Thomas Merton. (Here are all the highlights.) While he touched on climate change, he never uttered those two words. Will we hear them today? The timing couldn't be better, given the news that China—whose president Xi Jinping, is meeting with President Barack Obama on Friday—will commit to limiting and pricing carbon emissions (known as cap-and-trade). Follow the New Republic's Elizabeth Bruenig and Jeet Heer as they live-blog the event.