This article is part of an ongoing series exploring the tensions between, coalitions within, and futures of conservatism and libertarianism. We are looking at ideas that divide conservatives and libertarians, as well as ideas that bring them together.

Last week I confessed my disappointment with what the Laffer Curve has done to the debate about an ethical level of taxation. I said that the Laffer Curve “frames the conversation in terms of maximizing revenue for the government as if that was taken for granted as the main goal of tax policy.”

One of our well-read readers directed me to a blog post by Daniel Mitchell, a senior fellow at the Cato Institute, through which I found this video:

This was my introduction to the Rahn Curve. Though, as Mitchell explains, it basically is the same concept as the Laffer Curve except the x-axis is “government spending” instead of “tax rates.”

Again I see the significance in the research behind the Rahn Curve, and I do see how on a theoretical level it could be a useful tool in convincing a skeptic about the merits of limited government.

But I’m still not satisfied. Large government is not wrong because large government spending hurts the wealth-creation engine of the economy—which it does. It is wrong because it exceeds the obligations of government as defined in the social contract. I’ve made the case before that to argue for the moral superiority of free markets and limited government because of its ends ignores the very real moral superiority of its means. In a discussion about Matt Zwolinski’s Bleeding Heart Libertarians blog, I said:

To ignore this argument means that one must be willing to abandon his free market convictions if ever enough data is found to prove that a controlled market is more just in its results. Zwolinski admits this saying, “if it turned out that we were absolutely wrong about all of this, we would give up libertarianism.” But he dismisses the seriously of this condition, saying with a laugh, “we don’t think that is likely to happen.”

But data can be a dangerous thing. One’s convictions should run deeper than the numbers, because statistics can be interpreted to say almost anything. Not to mention that economic conditions tend to be cyclical. If one is willing to change their convictions along with changing statistics, is it accurate then to say that person has convictions?

And as I said last week:

Conservatives and libertarians agree that there is a minimal level of government operations required for a properly ordered society, though we may disagree on what that level is. We believe that any action of the government over and above their proper operations is a measure of tyranny. And any penny of taxation taken from citizens above the minimum level of revenue required for the government to conduct its proper operations is theft.

Elected officials should judge their proposed budgets with a strong fear of their actions. For if even one of their budget items is in excess, they have stolen and wronged their neighbors. Our task should be to identify what differentiates a proper fee for public goods from plunder.

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