Some related trivia, to give you an idea how amazing this is... Spain was ranked number one in the world... They hadn't lost a match in 35 games (the best run in soccer history -- they last lost a game in 2006). They'd won 15 straight (also a record). They hadn't even given up a goal in 451 minutes (since April 1st). They hadn't given up two goals (in a game) in 29 games.
The US, of course, was ranked fourteenth in the world going in.
The US national team had never before advanced to the finals in any FIFA tournament. And this after being all but eliminated from the tournament on the last day of group play.
This was one of the biggest upsets in US Soccer history.