By Tim Kelly Reuters TOKYO (Reuters) – Japan is worried that U.S. plans to pour billions of dollars into chip manufacturing to fend off China could finish off what's left of a Japanese semiconductor industry that once dominated the world. After "three lost decades", according to Japan's industry ministry, the country's share of global chip manufacturing has fallen from a half to a tenth as it leaked customers to cheaper rivals and failed to maintain a lead in cutting edge production. As China and the United States, driven by a trade war and security concerns, ramp up support for the…