I love VDH, but the short answer is simply “Because it will never be enough. The government could take every penny you earn and it would still never be enough.”
History shows that when Congress gets more revenue, the pols spend it.
http://online.wsj.com/article/SB10001424052748704648604575620502560925156.html?mod=djemEditorialPage_h
In the late 1980s, one of us, Richard Vedder, and Lowell Gallaway of Ohio University co-authored a often-cited research paper for the congressional Joint Economic Committee (known as the $1.58 study) that found that every new dollar of new taxes led to more than one dollar of new spending by Congress. Subsequent revisions of the study over the next decade found similar results.
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But no matter how we configured the data and no matter what variables we examined, higher tax collections never resulted in less spending.
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"Polls consistently find that a majority of Americans believe any new taxes will be spent by the politicians," pollster Scott Rasmussen told us recently in an interview.
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Our research confirms what the late economist Milton Friedman said of Congress many years ago: "Politicians will always spend every penny of tax raised and whatever else they can get away with."