Any time you try to talk about reducing the intrusive role of the state in human affairs, that's the question that almost always comes up at some point, right? We need state regulation of behavior, as symbolized by traffic lights, or there'd be, you know, chaos! Anarchy! The end of civilization as we know it!
So take just five minutes and have a look at the video below (thanks to David Zetland, at Aquanomics):
Now, of course, not that much hinges on traffic lights per se one way or another -- but, as in the question in the post's title, they're a symbol, and so the video above operates as a kind of parable, with a meaning beyond its face value. I don't want to make too much of it, but I think there really is a sense that, as we've become accustomed to, and dependent upon, an increasingly dense mesh of rules and regulations, requirements and proscriptions, our sense of what's possible becomes shrunken, our imaginations stunted. As a parable, this just asks that we question those acquired reflexes again, allow for the possiblity of regained, or even new kinds of freedom. Which might just make us not only more free, but also richer, and even safer. It's a thought.
Oh, and if you're interested in a little more context, here's Part 1: "Roads unfit for people".