I know that I am rather late to the meme, but seeing as the discussion of Obama’s professed cosmopolitanism is still going on, I want to add one quick thought, which is that perhaps the best reason to object to talk of being a “citizen of the world” is that it simply has no meaning. (My apologies if the points that follow have already been made.) Like patriotism, citizenship is a way of relating to a particular place and people: hence while I, for all of my own rootlessness, can clearly be counted as an “American patriot”, I have really said nothing whatsoever if I claim to have a patriotic devotion to “the world”. Similarly, it is only because American citizenship is not a privilege that is enjoyed by everyone that talk of such citizenship is any more contentful than claiming to belong to the class of all things that are members of classes. Put slightly differently, my point is that all meaningful speech is exclusive speech, and so a term can be significant only if it is possible for something in the domain of objects under consideration not to fall under it: since this is not true of the notion of a “world citizen”, it has no place in sensible political discourse. That is not, of course, to say that such talk is especially harmful or in any way exceptional (our politics traffics in vapid platitudes almost constantly), but simply that those who prize cognitive significance over empty signaling would do well to set themselves in opposition to it. Unless Sen. Obama had extraterrestrials in mind, the only thing his profession of global solidarity managed to accomplish was to make us all a bit dumber.
from The American Conservative