Not sure how you want this one answered flem-ish, but there are two things. The FIFA rankings show how well teams have done in recent competitive internationals, and USA progressed well in the recent World Cup. As to the question of why they have done so well, I suppose with a country as big as America, there's always going to be someone who is interested in watching and playing soccer, and in the national league they have players from al over the world, so the knowledge and experience that these guys have can only have a 'knock-on' effect. American soccer players have been in England for years. A prime example being Brad Friedel at Blackburn Rovers. Hope this helps.