I am reminded of Murray Rothbard, who offered:
The common separation between theory and practice is an artificial and fallacious one. But this is true in ethics as well as anything else. If an ethical ideal is inherently "impractical," that is, if it cannot work in practice, then it is a poor ideal and should be discarded forthwith.
How are we to determine if an ethical ideal is "impractical"? How would we determine what might be considered "practical"? Clearly an understanding of human nature is necessary, and it seems to me that a good place to start understanding human nature is to examine man's history.
In this, as you know, I have struggled through the political philosophy of Classical Liberalism and that of one of its offspring, Libertarianism. Both ideas are quite impractical – if not dangerous – absent an understanding of, appreciation for, and grounding in the history that brought forth these liberalizing (in the best sense of the term) philosophies.
So, count me in with Diodorus, Sturzo, EvKL, and Rothbard on this one.