In 2012, though, Steyer read an essay in Rolling Stone (“Global Warming’s Terrifying New Math”), in which Bill McKibben, the writer and climate activist, suggested that fossil-fuel interests had too much money at stake to let the political system do anything about carbon emissions. The only alternative, McKibben wrote, was a mass movement, and the only way to start a mass movement was to articulate a consistent, fact-based moral argument for change. At that moment, Taylor said, “Tom realized that the climate threat was near, present, imminent, massive — and aggravates every other crisis, whether it’s hunger or civil rights.” He had to do something different. So a few months later he and Taylor invited McKibben to the ranch for a war council.