At September’s Democratic National Convention, Bill Clinton roused his party when he said that Republicans, having left Barack Obama with a “total mess,” were now complaining that the president hasn’t “cleaned it up fast enough.” Clinton barely mentioned what got us into that mess: George W. Bush’s sharp tax cuts, mostly for the wealthy, which led more to financial speculation than to solid growth. He didn’t mention that job creation was slower in the years following the Bush tax cuts than at any other time in the postwar era. Nor did he mention that a substantial increase in taxes…