Now, having seen Sunstein's arguments elsewhere, I'm not terribly sympathetic to them since they seem on first glance to be little more than a thinly disguised argument for maintaining the information hegemony of the mainstream media. In fact, he is arguing that what used to be considered sensible -being familiar with both sides of an argument- should in fact be mandatory. He says,
...in a heterogeneous society, such a system requires something other than free, or publicly unrestricted, individual choices. On the contrary, it imposes two distinctive requirements. First, people should be exposed to materials that they would not have chosen in advance. Unanticipated encounters, involving topics and points of view that people have not sought out and perhaps find quire irritating, are central to democracy and even to freedom itself. Second, many or most citizens should have a range of common experiences. Without shared experiences, a heterogeneous society will have a much more difficult time addressing social problems; people may even find it hard to understand one another.
From his last sentence, it seems fairly clear to me that Professor Sunstein's concept of America and mine don't match up real well, since the whole point of America being organized as a federal republic is so that we can hold a heterogeneous society together and find different answers at the local and state levels for the various problems that confront society. I would advert to him that the problems of Chicago under Mayor Daley the Younger are not the same as those of Minneapolis under Mayor Rybak, and that handling the two cities in the same way would not only be foolish but wrong, since the two cities are very different from each other in terms of their population and history.
Professor Sunstein seems to believe that this is one nation, and should be homogenous in its culture and politics, but it has never been that way. Despite the best efforts of many people in both political parties over the last century, this is one nation only to foreigners, and sometimes not even to them. I'm not even certain that Garreau's book really sliced up America properly, since even within the Nine Nations he identifies, there are very real differences based on the impact of ethnic groups and their culture. Despite their proximity, there are very real differences in the way people from Iowa, Minnesota, North Dakota, South Dakota and Wisconsin think about matters political and social; still more so do they differ from their relatives in Texas, New York, Alabama and Hawaii.
The dividing lines don't fall just along political and ethnic lines. Religion has always had a strong influence on culture, and not always in the repressive ways excoriated by modern editorial page writers. Likewise, as Cobb points out, one of the results of the Sixties was greater tolerance for alternative lifestyles of all kinds. The Internet has been slagged by Sunstein and those like him for allowing people to retreat into sociopolitical cocoons, but it has also allowed people with obscure interests (obscure in the sense that they barely register in the national media) and unusual habits to come together and celebrate their uniqueness. It is also worth pointing out that one of the features of the blogosphere is that it feeds on the media and reacts to it, so that even the most phobic of Republicans would be hard put to it to escape all news of what Democrats think and do.
Which brings us around to Cobb's concern about eclexia. While he is correct about alternative lifestyles having become so large and organized that they have become subcultures of their own. I'm not sure people have become so in love with the new at the expense of the old. Instead, I find that the Internet gets used for a lot of pop culture archeology as well as legitimate historical inquiry. Still, there are people like that - they did a grand job of destroying much of Minneapolis' Gateway district, to say nothing of similar districts in other cities, in the name of urban renewal. Hollywood is full of them, of course. Sunstein's homogeneous culture would erase all of those things; we would become one nation of chinless little gray people, living in identical apartments, watching the same programs on TV and listening to the same music, all determined by people who Know Better. That's always the way utopias like that end, after all. Me, I'll take my chances. Whatever its other defects (and God knows it has plenty), 21st century America is wonderfully diverse and rarely has a dull moment - there's a reason people are dying to come here, after all.