Job creation is one of the biggest domestic-policy issues in this year's presidential campaign. But if elected, either candidate will find it hard to set the course of job growth in the $11 trillion-a-year US economy. Its direction is set by more than 130 million workers, long-running technological and demographic trends, and massive flows of trade, investment and spending not easily swayed by any one person -- even if that person is the president. There's no consensus on what's holding back the job market, but most of the big factors often cited by business economists -- high oil prices, technological changes, rapidly rising health care costs, debt-laden and overspent consumers, and a new cost-consciousness and aversion to risk among businesses -- are not under any president's immediate or direct control. This is one of the more insightful "Dr. Obvious Says" articles I've seen in USA Today. I've always been irritated at the way pols take credit and place blame for jobs numbers specifically and the economy generally. | 
