“Our religious institutions are the only institutions that are not completely implicated in the culture of materialism and growth,” said Bill McKibben, an environmental activist and a fellow at Harvard Divinity School’s Center for the Study of Values in Public Life. “The church can posit some other reason for human existence than the accumulation of material goods.” A number of theologians and environmental activists believe that it is time for mainstream religions to take up environmental causes. Religion is a natural fit, they say, because modern, industrialized culture is what is driving the global warming engine. And, as standards of living in developing nations rise, as hundreds of millions of new consumers embrace Western materialism, that engine will burn hotter. Minimizing the impact of global warming will take a moral crusade on a par with the 1960s Civil Rights Movement, McKibben said. Though that crusade can’t halt global warming, the difference it can make, McKibben said, will be well worth the effort.