USA appears to be very underated. They basically dominated the CONCAF or whatever the division is called qualifying. I think they led from beginning to end in the freakin 3 years it takes to qualify. Then they score right away against a team that was somewhat considered superior, played defense the entire match, gave up a late score and then scored again right away for the win.
Also, seems alot of these groups are the luck of the draw. Say US opens against Germany and loses and Ghana beats Portugal in the 1st game. Then it is a whole different group than what it previously was with current draw even though everyone plays everyone because teams may rest players once they have advanced and if you start off with 3 points like the US did, most USA fans are satisfied with a draw against Portugal (so will play defensive) because that will get them out of the group because of Portugal's lopsided defeat assuming Germany doesn't blow the US out.
I dont know all the rules of soccer, but if you wanted to play purely defensive and not even care about scoring, I don't see how another team could score. Couldn't you have 3 goalies. Yes I assume only one can use his hands. But alot of goals are soft misdirection shots where another leg in there could kick it out.