Cold War, hot planet: Could superpower rivalries derail climate change goals?

How serious are the superpowers in tackling the planet's climate emergency? In his speech to the United Nations General Assembly, Xi Jinping followed the lead of Japan and South Korea and pledged an end to China's financing of coal plants overseas. The United States put aside escalating tensions to hail the promise, but critics dismiss the announcement as low-hanging fruit coming from the nation that's home by far to the most domestic coal-fired power plants.