From Ludwig von Mises, Human Action, A Treatise on Economics, page 66/67: my emphasis.
There are no such things as a historical method of economics or a discipline of institutional economics. There is economics and there is economic history. The two must never be confused. All theorems of economics are necessarily valid in every instance in which all the assumptions presupposed are given. Of course, they have no practical significant in situations where these conditions are not present. The theorems referring to indirect exchange are applicable to conditions where there is no indirect exchange. But this does not impair their validity.
The issue has been obfuscated by the endeavors of governments and powerful pressure groups to disparage economics and to defame the economists. Despots and democratic majorities are drunk with power. They must reluctantly admit that they are subject to the laws of nature. But they reject the very notion of economic law. Are they not the supreme legislators? Don't they have the power to crush every opponent? No war lord is prone to acknowledge any limits other than those imposed on him by a superior armed force. Servile scribblers are always ready to foster such complacency by expounding the appropriate doctrines. They call their garbled presumptions "historical economics." In fact, economic history is a long record of government policies that failed because they were designed with a bold disregard for the laws of economics.
It is impossible to understand the history of economic thought if one does not pay attention to the fact that economics as such is a challenge to the conceit of those in power. An economist can never be a favorite of autocrats and demagogues. With them he is always the mischief-maker, and the more they are inwardly convinced that his objections are well-founded, the more they hate him.
By this definition, sycophants like Krugman et al aren't economists any more.
While this was written in 1949, it is valid today.
Governments which ignore the laws of economics, which at the end of the day are the laws of the market and of human action in those markets, are doomed to see their policies fail, and indeed fail miserably.
The war on poverty is one example: poverty won. You can't throw money at people and expect them to knuckle down and learn a trade or educate themselves out of poverty: they will, instead, behave as people did under the war on poverty.
Look, economists aren't heartless bastards, as much as the left thinks they are. We're the folks who can show you how to meet your political goals by working with markets. Ignore that at your peril.
Of course, we now see the "radical" critique, such as that of the post-autistic economics movement, about the failures of economics and how economists didn't see the bubbles building and didn't know when they would burst. I put "radical" in square quotes because it really isn't very radical, but rather reactionary (but that's for another day).
The thing is, there were those who saw the problems: no one listened. Economist have become so accustomed to being dismissed out of hand by the lawyers and accountants in charge - whose profound ignorance of economics is legendary - that we don't say anything any more, except, perhaps with each other.
Getting back to the point: the Obama Administration, for all its hope and glory, is no different from any other and is subject to the same laws of reality. Ignore the laws of economics and their policies will land on the trash heap of history with all the other policies that ignore economics.
Up to now, they don't even appear to understand that there are laws of economics. They don't care about economics, and yet do not realize that because of this, they will fail.
As they will.