The MLS was created to try to increase support for the world's game back in 1996. Though well intentioned, the MLS has hurt the development of US soccer as a force worldwide. The reasons why so many countries are better than the United States is that they have a majority of their players play in Europe.
In Europe, the Premier League in particular, the best talent from all over the world comes to compete. Players develop learning how to play the European way of the game and when they come back to play for their countries they can compete.
Brazil and Argentina do have their own leagues, but those serve more as developmental type leagues. Through those leagues, players get exposure and get signed by European clubs when they are 18,19, or 20. They don't get discouraged when players leave Brazil because they know they will become better players for it.
Americans usually leave themselves in America. This causes them to play against mediocre competition and learn a style of soccer that is ineffective in international play.
Though Landon Donovan can light it up in MLS, he was so useless in the World Cup you wouldn't think he was the same person. A majority of his goals came in friendlies against weaker international squads.
This isn't like the US basketball team, where we can play our own style of ball and cream people internationally(if we are motivated and have the right people). Soccer is not our sport. We didn't invent it. The way its played in European clubs is the best I have seen.
One person who shows that putting Americans in Europe works is Brian McBride. Though Brian McBride was successful in the MLS, his time at Everton and Fulham helped him to develop into the best striker on the US national team.
During the 2006 World Cup, McBride was the only player that performed well (the 4-5-1 formation however didn't allow him to shine).
Thankfully, many Americans are starting to go to Europe. Freddy Adu has signed with SL Benefica of Portugal and is playing at AS Monaco of France (on loan). I thought that Adu should have left for Europe at 16 instead of signing with DC United.
Eddie Johnson was signed for Fulham and is playing at Cardiff City. Dempsey has with Fulham, and Demarcus Beasley is with Rangers and starting in the Champions League. Hopefully this trend will continue.
I know that European clubs don't look vary favorably on Us players but, with time, US players will show their worth in Europe causing clubs to look to America for talent.
I am not saying that the MLS has to be destroyed, but there should be more encouragement for the best talent the United States has, when it comes to soccer, to play in Europe. It can only give the US better players, a better team, and respect as a power in international soccer.