As Stan Collender, a Beltway budget guru, explains, Crook isn’t saying something that others haven’t already said.

But the fact that Clive is now willing to go where others have boldly gone before is an important indication that the public debate is now changing and that a tax increase is becoming a topic for polite conversation. It might not yet inevitable but it’s definitely becoming more acceptable.

Indeed, here’s Crook in the FT in December 2009, recognizing that revenue needs to go up but unwilling to call for the tax increases he’s advocating today:

Mr Obama ought to see the country’s broken income tax system as a stroke of luck. It is so complex, so distorting, so shot full of exemptions and deductions, that by broadening the base the US could raise significantly more revenue without raising marginal tax rates. A Reagan-style flattening of the tax system could pay for health reform without impairing economic efficiency. Extra decency, and no less vibrancy. Civilisation without the sedative.

Holly Yeager is CJR's Peterson Fellow, covering fiscal and economic policy. She is based in Washington and reachable at holly.yeager@gmail.com.