And then Niskanen, looking over 25 years of budget data, noticed something about STB: It didn’t work. In fact, attempts to starve the beast by tax cuts seemed to lead to increased federal spending.

Niskanen looked at both spending and taxes as a percentage of GDP. On average, he found, if federal revenues declined by 1 percent, federal spending increased by 0.15 percent. When revenues rose, on the other hand, relative spending decreased. A further study in 2009 by another Cato economist, Michael New, came to the same conclusion after the gluttonous administration of George W. Bush. Under Bush and his mostly Republican Congress, new benefits like subsidized Medicare drugs and increased federal education spending followed on the heels of large tax cuts.

Niskanen’s explanation for the failure of STB was straightforward, a conjecture based on standard economics: When you cut the price of something, demand for it will increase. Lowering taxes without lowering benefits meant that taxpayers were getting the benefits at a discount. The government made up the true cost with borrowed dollars that future taxpayers would have to repay. There was a big difference, Niskanen said, between a kid on an allowance and the federal government: The government has a credit card with no debt limit…

Reagan, Friedman, and other early advocates of STB had counted on something that never materialized. They had assumed that as the debt piled up to finance annual bud- get deficits caused by free-flowing benefits, public outrage would force politicians to restrain spending without raising taxes. Yet we’ve had the deficits and the borrowing, in amounts that would have left Friedman and Reagan agog; what’s been missing is the outrage.