Torben Lutjen, a political scientist at the University of Dusseldorf in Germany, is researching political polarization in the United States as a visiting scholar at the University of Wisconsin-Madison….After returning to Germany for the summer, Lutjen, 37, is back in Wisconsin yet again. This time he?s researching conservative Waukesha County. Lutjen believes the two counties ? Dane and Waukesha ? offer a special glimpse into a trend of political polarization that is gripping the United States and puzzling observers in the rest of the western world.