Michael Shellenberger was named "hero of the environment" by TIME Magazine in 2008. He is an environmental expert who has spent his career fighting for policies that will protect the earth. But when he realized how terrified his daughter had become of climate change and the alleged real-life consequences scientists say will come from it, he gained the needed courage to speak out. His new book, "Apocalypse Now," dives into and exposes the new religion of climate change activism. In this clip, he explains to Glenn what's driving the movement.