I've always thought it a little curious that the U.S. Republican party seems to consistently talk about small government, but implement big government. William A. Niskanen, the chairman of the libertarian Cato Institute, thinks he knows why. I'm not normally a fan of the Cato Institute, but I must admit that Niskanen's thesis is appealing and he's got some data to back it up.
Jonathan Rauch discusses Niskanen's theory in the June 2006 Atlantic Monthly:
Reagan and his supply-side vanguard saw a way to break the jam—or, more precisely, two ways. First, some argued that tax cuts would so energize the economy as to pay for themselves. That claim was widely controversial, even among Republicans (Reagan’s then-rival George H. W. Bush called it “voodoo economics”), and it proved mostly wrong. Less controversial, but in the end more important, was the claim Reagan lobbed at Anderson. Often called the Starve the Beast hypothesis, it held that tax cuts shrink the federal Leviathan by starving it of funds. Tax cuts need not await spending cuts because they would cause spending cuts.
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Even during the Reagan years, Niskanen was suspicious of Starve the Beast. He thought it more likely that tax cuts, when unmatched with spending cuts, would reduce the apparent cost of government, thus stimulating rather than stunting Washington’s growth. “You make government look cheaper than it would otherwise be,” he said recently.
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Niskanen recently analyzed data from 1981 to 2005 and found his hunch strongly confirmed. When he performed a statistical regression that controlled for unemployment (which independently influences spending and taxes), he found, he says, “no sign that deficits have ever acted as a constraint on spending.” To the contrary: judging by the last twenty-five years (plenty of time for a fair test), a tax cut of 1 percent of the GDP increases the rate of spending growth by about 0.15 percent of the GDP a year. A comparable tax hike reduces spending growth by the same amount.
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By turning a limited-government movement into an anti-tax movement, conservatism has effectively gone into business with the Big Government that it claims to oppose. It is not starving the beast. It is fueling the beast’s appetite. And the beast has a credit card.