Sitting at the table doesn't make you a diner, unless you eat some of what's on that plate. Being here in America doesn't make you an American. Being born here in America doesn't make you an American.What's an American? Consider: All-American. African-American (not to mention Asian-American, Italian-American, Cuban-American, and so on). American culture (sometimes said to be an oxymoron). The Ugly American.
The idea of being identity-American implies there is a core concept in "American" which modifies whatever is in the "identity". A problem of multiculturalism may be to overstress that first "identity" to the detriment of the commonality of "American". Thus, the identity-politics reflects not a truly different culture, but is a metaphorical way of expressing dissatisfaction with the injustice of divisions within our society. A heavily restricted set of roles within the nation is thought of as being a not a part of the overall society, a separate nation.
But being one nation does not mean the absence of internal divisions. Few countries are homogeneous. America is notable for the wide range of its population, but such a spread is not unique. There is a difference between uniformity and commonality. If we assume for the sake of argument, that there is a such a thing as a core culture, then more homogeneous countries simply have less expressed beyond that core when compared to more diverse ones.
It's notable that the political aspirations of various supposedly different American cultural groups, even when expressed in what might seem to be the most divisive group-politics, aim almost entirely towards simply bettering the member's positions within the society, rather than radical re-arrangement. Even the separatists often want to simply replicate nearly everything in the society from which they are supposedly breaking off, but with their group more widely distributed within those structures.
This sort of overall unity is thrown into high relief by comparison with a situation such as the area which once was Yugoslavia. There, the divisions present turned into a multilateral war which utterly fragmented the country. Even if the American Civil War is thought to be roughly comparable, the ultimate outcome for that case was greater union. Similarly, the civil-rights upheavals a century later eventually resulted in greater social integration than had been seen previously, as formal segregation was made illegal. The tensions we see now can easily be attributed to the stress of having to deal with integration in practice, which is not a trivial achievement. So though our society may seem to be more divided than decades ago, what we see is arguably one of the more difficult aspects of actually being more closely knit as a nation.
In short, there is a vast difference between a large amount of dissent or dissatisfaction within a common framework, and a desire to destroy a social framework view as alien and worthy of war. The relative peacefulness of America, by global standards, testifies to a common core which proves the existence of a nation.
Seth Finkelstein is a computer consultant in Massachusetts who posts regularly to Usenet and private mailing lists on political and censorship-related topics. He has contributed several articles to The Ethical Spectacle.