There's a growing trend among libertarians to self-identify as liberals and to distance themselves from political conservatism. This trend has precedents; the economist Friedrich Hayek wrote an essay in 1960 entitled "Why I Am Not a Conservative," for example. As a previous blog post of mine might indicate, although I consider myself a libertarian, there are several things about libertarianism, at least as it is commonly understood, which I find problematic. Specifically, many libertarians are committed at the level of ethical theory to an axiomatic principle of liberty or to a theory of natural rights; this puts them in opposition to consequentialist ethical analysis, which I regard as important, particularly with respect to questions of social justice--a concept which many libertarians, including even good old Hayek, regard with suspicion or skepticism. Openness to taking social justice seriously is part of what makes for a genuinely liberal strain of libertarian; other parts include cosmopolitanism, a secular worldview (or at least a secular approach to politics), opposition to war and militarism, opposition to the war on drugs, and support for the rights of gays and other people regarded as deviant or inferior by most conservatives.
Will Wilkinson, who has been an outspoken liberal libertarian for some time now, recently blogged about Bleeding Heart Libertarians, itself a new group blog by libertarian philosophers with an interest in neoclassical liberalism, combining libertarianism with contemporary liberalism, and libertarian social justice. Special mention should go to one of the blog's contibutors, Roderick T. Long, who has been an energetic advocate of "left libertarianism" for some time now.
On a related note, Peter Jaworski, a faculty member in the philosophy department at Bowling Green State University (where I currently teach part-time), recently blogged about the liberal libertarian phenomenon, including a discussion of the ethical issues underlying questions of social justice, and why an ethical principle of social justice does not by itself provide the justification for a welfare state.
Personally, my libertarian political beliefs have been a constant source of frustration and embarassment. Culturally, I am much more liberal than conservative, so most of my friends have been liberal, and as a consequence they have been either intolerant of or at least uncomfortable with my libertarianism, should I ever bring it up. Libertarianism is simply not acceptable among liberal social circles. As is often the case when it comes to political beliefs, a libertarian is usually regarded by liberals as being, not just ignorant or mistaken in his political beliefs, but downright morally defective on account of them. It's very difficult to have a rational conversation with anyone about politics (or religion, for that matter), even with someone who is very intelligent and relatively broad-minded. This probably has something to do with the way the human mind works--specifically, the psychology of group-based identity, or in-group / out-group thinking (about which there has been a lot of fascinating psychological research in the last ten years). A person with divergent political beliefs is regarded not just as wrong, but as a threat to the faction with which we identify, and by extention a threat to ourselves and those we care about. You can imagine the political disagreements among our hunter-gatherer ancestors as often being a matter of life and death, and it still feels that way today, even when our life is not in fact at stake.
In any event, I'm glad that there are other libertarians out there of a decidedly liberal bent--in terms of their cultural proclivites, political views, and even aspects of their ethical theory (insofar as most conservative libertarians seem to be defend theories of natural rights). I regard libertarianism as a progressive political philosophy, and I hope that more people in the general public will start to view it that way as well, even if they continue to disagree with it.