Paul Krugman’s quit his NY Times column and although he hasn’t said it in so many words, it’s most likely because he felt constrained from saying what he wants to say the way he wants to say it. He does have a newsletter and he’s already bringing the fire: Once upon a time a Republican president, sure that large parts of federal spending were worthless, appointed a commission led by a wealthy businessman to bring a business sensibility to the budget, going through it line by line to identify inefficiency and waste. The commission initially made a big splash, and there were desperate attempts to spin its work as a success. But in the end few people were fooled. Ronald Reagan’s venture, the President’s Private Sector Survey on Cost Control — the so-called “Grace commission,” headed by J. Peter Grace — was a flop, making no visible dent in spending. Why was it a flop? There is, of course, inefficiency and waste in the federal government, as there is in any large organization. But most government spending happens because it delivers something people want, and you can’t make significant cuts without hard choices. Furthermore, the notion that businessmen have skills that readily translate into managing the government is all wrong. Business and government serve different purposes and require different mindsets. In any case, the Grace commission’s failure taught everyone serious about the budget, liberal or conservative, an important lesson: Anyone who proposes saving lots of taxpayer money by eliminating “waste, fraud and…