Via Megan comes this article about redesigning traffic intersections in Holland.  They redesigned the intersections to remove signs and traffic restrictions...

As I watched the intricate social ballet that occurred as cars and bikes slowed to enter the circle (pedestrians were meant to cross at crosswalks placed a bit before the intersection), Monderman performed a favorite trick. He walked, backward and with eyes closed, into the Laweiplein. The traffic made its way around him. No one honked, he wasn't struck. Instead of a binary, mechanistic process--stop, go--the movement of traffic and pedestrians in the circle felt human and organic.

A year after the change, the results of this "extreme makeover" were striking: Not only had congestion decreased in the intersection-- buses spent less time waiting to get through, for ­example-- but there were half as many accidents, even though total car traffic was up by a third. Students from a local engineering college who studied the intersection reported that both drivers and, unusually, cyclists were using signals-- of the electronic or hand variety-- more often. They also found, in surveys, that residents, despite the measurable increase in safety, perceived the place to be more dangerous. This was music to Monderman's ears. If they had not felt less secure, he said, he "would have changed it immediately."
...
When thinking about human behavior, it makes sense to understand what people perceive, which may be different from how things are, and will almost certainly be very different from how a removed third party thinks them to be. Traffic accidents are predominantly caused by people being inattentive. Increase the feeling of risk, and you increase the attention. I know when I am in traffic on my bike, I'm hyper-vigilant, and this has made me a better car driver.

This is an extremely powerful and important idea... and one that goes against the heart of all political campaigning and most government ideas.  Bruce Schneier talks about this often on his blog.  The point that we need to feel insecure in order to be more attentive, and therefore safer, is extremely important.  However, most endeavors aimed at making us safe do the exact opposite.

You can look at the majority of airport security to see my point.  Hardly any of the measures being taken actually make us safer, but they do make us less vigilant because we think the TSA is doing its job.  Social Security is meant to make you feel comfortable about your retirement, and yet it leads people to save less for the future, and therefore dooms them in their old age.

And yet, if people don't feel safer then they will think that their politicians aren't doing their job, whether they actually are safer as a result or not.  People may choose to then change something that works, based solely on this perception, and often times do.  Politicians therefore have a strong incentive to create laws that create the perceptions, rather than the reality, of security... if for no other reason than to be re-elected.

How do we work around this security paradox?  I haven't a clue... but a good starting point is recognizing its existence.