LOWER CASE, PLEASE
Randy Barnett has been wondering whether he should continue to capitalize Libertarian when he refers to the political philosophy, as opposed to the political party. He should not. Political parties and religions get capital letters. Political philosophies do not (unless they are named for people or places). Libertarianism, as Randy explicitly understands it, is neither a religion nor a party but a strand of liberalism, a philosophical tradition that isn't capitalized either.
It has always infuriated me that the newspaper like the LAT, which are staffed with copy editors who know these rules, insist on capitalizing Libertarian--the better to marginalize a broad political philosophy by treating it as a party or sect. Being a libertarian is like being a republican or a democrat.
Follow the link above, or just go to Volokh Conspiracy, to read the thoughtful discussion Randy has sparked on libertarianism and foreign policy. I wholeheartedly agree that you cannot derive much about foreign policy from libertarian first principles. As John Locke observed, kings live in the state of nature. (I'm much more of a consequentialist, empiricist classical liberal than Randy. But he demonstrates that even what I call deductive libertarianism can't tell you much about how a libertarian state should behave toward other states.)