Soccer in America has never been treated like any other sport.  In a country that can’t even agree on what to call the game, it has been alternately loved like an underground band, ridiculed as a poisonous foreign import, and, for most of its history, roundly ignored.  But if the U.S. is in a position to co-host the largest ever World Cup over the course of the next five weeks, it’s because of a bubbling undercurrent that has sustained the game in America for nearly a century. Today, it boasts one of the best attended domestic leagues in the world,…