This was supposed to happen in the 80's after the NASL had that surge with Pele and Beckenbauer et al. What happens the number of kids playing soccer doesn't translate to interest in the pro game and the league collapsed.
What happens more often than not is soccer kids get more interested in other sports.
Believe the last thing the world wants is a US that gives a **** about soccer.
The difference between now and the early 80s is night and day. Despite your anecdotal observations and media-fed editorials there is a massive difference between then and now.
Back then they decided the best way to build the house was start with the roof. Since before 1994, the development arm of US soccer has changed dramatically and actually worked on the foundation.
There was a linking up with the German federation to help develop the youth system. What has happened is the dramatic improvement in coaching at the grass roots level, a big increase in facilities (including funding), and the creation of higher level feeder leagues throughout the pyramid of play that push players towards the top (ie college ranks, A-League, Olympic Development Programs, various development leagues). Additionally, the training of the top youth players has followed the same plan that the top nations use. Take a look at the results of the international youth teams and you 'll see the dramatic improvement.
The number of American players in Europe continues to increase, and relative success internationally shows the improvement in the US game. This success didn't exist in the 80s but it does now. The US has been to every World Cup since 1990. England hasn't, and when they have been there, the US has had arguably more success.
I freely admit that the numbers playing the game at the youth level are somewhat irrelevant. Soccer is a great participatory sport because it's cheap and easy. But the popularity in watching the game has increased and will continue to improve with the ability to watch the international game (domestic leagues) with greater ease. This translates to more players who want to reach as high a level of play as possible, and with the sustainability of the MLS they now have somewhere to aim if they can't quite make it in the EPL, Italy, etc, etc.
Did you read the
link provided by TT about the overall tv deal? They're also poised to sign a deal with Fox the extends beyond just MLS games. Sure, ESPN is spending less than they would if they were covering hockey, but don't fool yourselves. They didn't just pick the sport out of a hat and decided to go with it.