America will never be top-shelf on the pitch because kids don't play the sport for fun. Anyone born in the 80's or 90's can agree with this: did you ever see a bunch of ADOS or white kids (no immigrants) just randomly go out to a soccer pitch and start playing "just because?" I've seen us play hoops, football...even baseball or running relay races against each other. The only kids that get out and just play soccer for fun are African-born/second generation black kids and Hispanic kids in the U.S.
The average suburban ADOS/white-American kid only plays soccer as part of a league. In hoops, a lot of the cool moves you learn come from unorganized fooling around on the blacktop. Soccer is much the same way. Any good coach can teach you tactics, fitness and strategy. What they can't teach you is 'feel' and 'touch.' That's why the American teams are always super fit, fairly quick and athletic but don't really have a feel for the game the way other teams do. It would be like taking young Adrian Peterson or Usain Bolt and putting them on an NBA court during Game 1 of the NBA Finals. No matter how athletic they are, they'd look completely lost out there and be a liability on offense AND defense.
Having said that......if soccer became ingrained in our culture, I think we'd have a world class side for the men's national team. If our freak athletes start playing soccer from an early age and they live/breathe/eat soccer like kids in other countries AND THEN receive top-notch training, we'd dominate. Pretty much any point guard or cornerback/safety would be ideal in terms of size/speed/change of direction etc. Again though, the key is being fully immersed in the sport from the jump. Not sure we'll ever have that level of commitment in our culture.