Brad DeLong takes on the Kevin Hassett, Glenn Hubbard, Greg Mankiw, John Taylor position paper defending the Romney economic "plan". Mostly bullseyes, I think, though there'd be a lot of food for thought in delving into things further. I particularly liked Brad's evisceration of HHMT's appeal to the supposed success of supply side notions such as those Romney currently leans on, during the Reagan years:
And the embarrassing reality underlying the Reagan years 1981-1989 is that the rate of growth of America’s productive potential, as estimated by the Congressional Budget Office, was no faster over 1981-1989 than it had been over 1973-1981. If Reagan administration policies were truly aimed at boosting American growth, they failed—in large part because of the drag placed on investment by the high real interest rates that businesses had to pay in the Reagan years, as they competed for scarce pools of capital left over after the U.S. government had financed the Reagan deficits.
The mythology and hagiography surrounding Reagan has done a lot of damage to popular American political and economic thinking over the most recent decades, in my opinion, and in my view we need a political party, political leaders, and opinion leaders willing to take it on much more aggressively. (I would prefer, in Brad's comparison, to see the period 1971-1980 (inclusive) rather than 1973-1981, though I doubt it would change the comparison much.)