The millions of Americans who lost factory jobs over the past decade may find this hard to believe, but U.S. manufacturing is coming back to life. They say manufacturing’s future is getting brighter because of “fracking” — an increasingly popular drilling technique used to recover natural gas from shale formations. Fracking is helping guarantee factory owners access to cheap, reliable and abundant energy sources. People landing fracking-related jobs have gotten a lot of media attention in recent years. But many more workers are quietly finding paychecks in factories as manufacturers start to take advantage of lower natural gas prices.