The news that Mexican-American pop sensation Jenni Rivera died in a plane crash last weekend was matched, in many corners of America, with the news that she had ever existed. Rivera, a California native, had sold an impressive 15 million records, largely in Mexico and in the American West and Southwest. But because she appealed to a particular population — she sang largely in Spanish, in a tradition known as “la banda” — she operated outside the radar of the mainstream media, with its narrow definitions of American pop music.

To some degree, the 43-year-old Rivera’s odd mix of fame and obscurity is a sign of enduring divisions in our nation. It’s also a reflection of changes in the music industry, once more of a unifying pop force in American culture, which has gravitated increasingly toward exploiting niches.