A dollar spent on tax cuts costs more than a dollar over the long run, a lot more.

With regard to Mark Thoma's August 27th post, "The Whole Analysis Sounds Pretty Fishy":

So the the right wing propaganda tank, Tax Foundation, claims that tax cuts recover up to 40% of their costs through so-called dynamic effects, while Bush's own Treasury Department estimated less than 10%.

Even if it actually were 40%, are tax cuts a good idea, especially tax cuts going predominantly to the rich and extremely rich? They're still costing the government 60% that can't go to many extremely high social return projects that the free market won't undertake due to market imperfections that are well established and proven in economics (real, scientific, academic economics, not screaming talk show host, propaganda tank economics), like externalities, asymmetric information, impracticalities of patenting, large economies of scale and monopoly issues, the zero marginal cost of information and ideas, the inability to price discriminate well, and many more available in any university introductory and intermediate economics texts.

Suppose we consider continuing Republican policies and spending another 1 trillion on tax cuts for the rich. Even if 40% were recovered (and in the long run, as opposed to just looking at short run effects, the dynamic effects go in the opposite direction -- a dollar in tax cuts ends up costing a lot more than a dollar in government revenue if that means a dollar, or even 60 cents, less in investment in high return government projects.).

The vast majority of the tax cuts, it has been shown, will eventually be spent on consumption items of little long run investment value -- leaving little to show or to grow. If instead, even just 60% of that 1 trillion were spent by the government on extremely high social return investments like infrastructure, education, basic scientific and medical research, alternative energy, etc., then 10 or 20 years from now that 600 billion could result in many trillions, or even tens of trillions more in national wealth, as opposed to having the whole 1 trillion spent on rapidly depreciating Ferraris and yachts, and ultra luxury vacations and other things for the rich that have little or no productive value.

In the long run, a dollar spent on tax cuts for the rich, instead of badly needed social investment puts us one more step closer to losing our status as the most wealthy and modern nation, and over the long run, like any other decision to increase frivolous consumption at the expense of high return investment, it costs us a lot more than a dollar, not less.