IBT: World leaders have been trying to forge a global treaty on climate change for more than two decades. But persuading countries to abandon profitable fossil fuels -- and instead spend trillions of dollars on new technology and environmental protections -- has proved nearly impossible. The Kyoto Protocol, negotiated in 1997, expired two years ago with little discernable impact on greenhouse gas emissions. (The United States signed, but never ratified, the agreement.) Attempts to work out a successor...