WASHINGTON - The nation's worst blackout began with three power line failures in Ohio and should have been contained by operators at FirstEnergy Corp., a three-month government investigation concluded Wednesday. The report by a U.S.-Canadian task force said the FirstEnergy operators did not respond properly, allowing the Aug. 14 outage to cascade, eventually cutting off electricity to 50 million people in eight states and Canada. The task force also cited outdated procedures and shortcomings at a regional grid monitoring center in Indiana that kept officials there from grasping the emerging danger and helping FirstEnergy deal with it. "This blackout was...