This paper shows a variety of evidence that members of Congress are ideologically consistent. Based upon the roll call voting record, once elected to Congress, members adopt a consistent ideological position and maintain it over time. There may be changing minds, but they are not in Congress....

The idea of America as politically polarized—that there is an unbridgeable divide between right and left, red and blue states—has become a cliché. What commentators miss, however, is that increasing polarization in recent decades has been closely accompanied by fundamental social and...