Barack Obama courted manufacturers in Michigan Wednesday, touting proposals to boost both green energy and the auto industry. He talked up a plan to auction carbon credits and use the funds to boost clean technology (and, in turn, green jobs), and said he would help the U.S. auto industry get back on its feet while encouraging investment in hybrids, electric vehicles, and other fuel-efficient cars. “I don’t think that we need to give up on manufacturing,” he told the Detroit Free Press. “We need to find new sources of manufacturing jobs. And I think creating green energy jobs and helping the auto industry to retool — those are all areas with enormous promise.” Obama’s speech excited some in Silicon Valley, who are anxious to see more government backing for clean-tech enterprises.