Party and Ideology

Anyone who has watched the bitter competition between the Democrats and Republicans in Congress in recent years, or the fight to win the Republican nomination for President this year, might be wondering how to explain the current political party system in the United States. It looks like a period of deep ideological cleavages between the parties, and pretty strict enforcement of some form of ideological correctness at least in one of them. Yet for decades or even centuries scholars of politics have argued that ideological divisions were relatively weak in our elections and legislative process. What is happening, and what has happened?
This may be the central question for understanding the current state of American politics. Professor John Zaller of UCLA is one of the leading and most original scholars of both political parties and public opinion in the country.