Mild Republican-bashing aside, Jonathan Chait has done a good job of laying out how Mitt Romney and Barack Obama might handle the expiration of the Bush-era tax cuts and the automatic spending cuts that are scheduled to go into effect at the start of 2013. Matt Yglesias embraces Chait’s premise that an Obama victory could usher in a major victory of the U.S. center-left, as it would set the stage for a sharp increase in federal taxes and a sharp decrease in defense expenditures — yet he expresses uncertainty as to whether the president would actually follow through.