When Americans imagine cultural diversity, we often have in mind diverse identities. When we argue about cultural diversity, the arguments are often about identities, too. Critics of cultural diversity worry that Americans focus too little on common experiences—as Americans, as human beings—and dwell too much on particular racial, sexual, or gender identities. Proponents of cultural diversity seek out the particularity and celebrate diverse identities. A fascination with identity has either made Americans tribal or else has opened Americans’ minds and given voice to the silenced. Either way, big things are at stake, not just university course syllabi, or Columbus Day ceremonies, but the way Americans think about a collective heritage. No wonder, then, that cultural identity claims have been loud and impassioned, and the scholarly debates about them heated.