In his most recent budget request, the president proposed letting the top two income tax rates revert to 39.6% and 36%, up from 35% and 33% today. He also called for an increase in the capital gains and dividend rates to 20% that high-income households pay, up from 15% today. And he would reduce the value of their itemized deductions and personal exemptions.

All told, those proposals — which would affect individuals making at least $200,000 and couples making $250,000 and up — would reduce deficits by just under $1 trillion over 10 years.

That’s only about a third of the deficit reduction that would occur if lawmakers just let all of the Bush-era tax cuts expire…

“You’d have to raise rates an awful lot on the wealthy,” Williams said. And by that he meant to heights that would be neither politically nor possibly even economically feasible.