The billionaire brothers Charles and David Koch are known for funneling vast donations into Republican campaigns in the United States. But what impact are the Koch brothers having on global warming? As the United States is accused of blocking progress at the U.N. climate talks in Doha, a new report says the Koch brothers may be the biggest force behind the climate stalemate. The Kochs run oil refineries and control thousands of miles of pipeline, giving them a massive personal stake in the fossil fuel industry. Researchers say they have also funneled tens of millions into climate denial science, lobbying and other efforts to derail policy that could lessen the impact of global warming. We’re joined by Victor Menotti, executive director of the International Forum on Globalization.