Andrew Sullivan notes a recent study that demonstrates a negative correlation between level of congressional pork and the number obsolete bridges within a district.
This result may seem counter-intuitive at first, but it is not. Pork barrel politicians get credit for building new bridges, not fixing old ones. But the more new bridges you build, the more old bridges your district will eventually have. Assuming that a politician cares more about building than fixing, this is the inevitable result.


