As Democrats survey the political wreckage of the last three years, the temptation to imagine more pleasant alternate realities is irresistible. What if Hillary Clinton had been elected president instead of Obama? Would events have played out any differently? Or, even more tantalizingly (albeit technically impossible), what if the Big Dog himself, Bill Clinton, had been in charge the last three years? Would he have done a better job fixing the economy? Been more effective knocking heads with the Tea Party? Established himself as a better bet to win a second term?