Before retiring from his career as an oil and gas engineer, John Allaire bought a slice of paradise: more than a half-mile of oceanfront in Louisiana’s Cameron Parish, backed by 300-plus acres of marsh where he could gather shrimp and watch bobcats prowl. “This was my little place to be quiet and stargaze and fish and hunt,” he says. Nowadays a constant rumbling disturbs his peace. A mile away, a company called Venture Global cools natural gas to -260 degrees Fahrenheit, converting it to a liquid to be shipped overseas. At all hours, on a site that not long ago held dozens of acres of prime Eastern Black Rail habitat, flare stacks shoot flames sky-high. “At night it’s lit up like Las Vegas over there,” Allaire says. So much for the golden years he imagined. Allaire and his neighbors now live at the epicenter of a boom in liquefied natural gas (LNG) exports. In the past decade energy firms have built five terminals along the Gulf Coast, and around 20 new plants...