In order to create great soccer players, they have to start playing very young, they have to love the game, and they have to play for thousands of hours as children. Our kids dabble in different sports up until High School when they choose one sport. You can't have kids playing a different sport every 3 months and expect them to be great soccer players. Soccer is like Boxing in sense that it looks easy, but it's very difficult to become elite. When you see great Boxers, they usually start when they are like 5-8 years old. You rarely see a great Boxer who picks up the sport late in life ( Sergio Martinez/ Ernie Shavers types are the exception). Same thing with Soccer. The USA's answer to sports is to "out athletic" your opponent. Soccer is all about skill. Look at Barcelona when they were whipping everyones ass. They Had/Have Xavi, Iniesta, and Messi. Three Dudes who if you saw walking down the street would look like everyday schmoes. They are short, Messi has some sort of dwarfism, yet are extremely skilled and dominate.
Youth development in the US is horrible. There are too many different youth organizations and they don't offer legit coaching. The USSF/MLS should develop a youth league and corner the market like little league did with baseball, and Pop Warner did with football. They could set up a curriculum for kids to follow in elementary and middle school. Horst Wein talks about children should play small sided games to develop ball skills. 3v3 up until 9 years old, 5v5 10 year olds, 7v7 11-12 year olds, 8v8 13 year olds, and finally playing 11v11 when they turn 14. They say that the reason Argentina and Brazil are so good is because they have their kids playing futsal before moving up to regular soccer. Real Madrid and Barcelona also have their youth teams play small sided games. When you develop the youth they learn to understand the game, and they learn to love the game. So you are creating future players and fans.
Once the kids reach High School they could be eligible for a youth academy. The MLS also needs to develop legit youth academies. Most Teams have an academy but I don't think they are professional. Our kids are taught to be good enough in their sport to possibly play college ball. Footballers from around the world start going to academies usually in their early teens and learning to be pros.

to college ball.
The US also does a bad job of including kids from the inner city/low Income households *cough* black and latino kids *cough*. In this country Soccer is seen as a rich kid sport like ice skating, gymnastics, tennis. Usually you have to pay big bucks to play in a top local club. My sister played for a traveling team in middle school and the cost was crazy. Good thing they didn't charge my parents to play. Instead of having kids invest in the sport, the sport (USSF/MLS) should invest in the kids.
To me soccer is the best sport to get your kid into. It gets them in great shape, it's relatively safe, and you don't have to be tall (basketball) or big and strong (football) in order to play at the top levels. I think it's funny when parents invest their child's time in basketball and football, and they end up being 5'9'' 160 lbs. I could care less about baseball and hockey.