The full moon is out, and I'm about to change into my werewolf form and run off into the night, performing various ethical deeds. But while I'm still a mild-mannered philosopher, let me point anyone interested in political philosophy to Elizabeth Anderson's latest post. It contrasts two kinds of freedom -- freedom as non-interference and freedom as expanding one's opportunity set. The former is the one emphasized by libertarians, but the latter is the one that's worth caring about.
If the only kind of freedom that matters is that no one intentionally interfere with one's formal freedom of action, and not that one's opportunity set be large and full of worthwhile options, then freedom-lovers would have to oppose traffic laws, stop lights, and so forth, for interfering with freedom of movement... By contrast, if we give up certain formal freedoms--to run red lights and stop signs, to drive indiscriminately across lanes--we get in return a vastly expanded opportunity set, including the ability to actually get to places one wants to go, more safely and quickly than if we hadn't given up those freedoms. The point of formal freedom of movement--the right to move around, without coercive interference by the state or other people--is that it is instrumental to expanding actual opportunities to move around where one wants to go. Merely formal freedom of movement, with nowhere to move to, or nowhere worth moving to, is not an end in itself. Different configurations of formal freedom of movement--different traffic laws--are justified by the extent of the opportunities for safe freedom of movement they enable.