National Public Radio: A radical shift in the world energy picture is raising environmental concerns in the United States. Until recently, the U.S. had been expected to import more natural gas. But now, because of controversial technologies like "fracking," drillers are producing a lot more domestic natural gas; so much that prices are down along with industry profits. And drillers are looking overseas for new customers. Whether the United States should export some of its newly abundant supplies of natural gas is a controversial...