Tax Fairness and the Presidential Campaign

Is America's tax system fair? President Obama calls progressive taxation "the defining issue of our time," an question of "economic fairness." The Republicans call it "class warfare." Elizabeth Warren, who helped the Consumer Protection Bureau and is now a Democratic candidate for the US Senate, recently spoke out against the tax disparity on Jon Stewart's The Daily Show. Should the rich pay a higher tax rate?  Is that a penalty for achieving the American Dream?