How Do US Senators Cluster?

We often hear remarks like the one here from William A. Galston, a Senior Fellow in Governance Studies at the Brookings Institute, claiming that polarization in the US Congress is at an all-time high WA10. It is easy to understand why. Such portraits are often made in the popular press, and mainstream media outlets in the United States often work to amplify these differences. If we think of legislative morass as a by-product of this polarization, then we could look to legislative outcomes as a rough measure of polarization. In the 110th Congress nearly 14,000 pieces of legislation were introduced, but only 449 bills, or 3.3%, actually became law PS08. In fact, of those 449 bills, 144 simply changed the name of a federal building.