Soccer has been the "sport of the future" for seemingly 30 years. It's advanced a little in popularity, but not nearly to the extent that some would have predicted.
To me, it probably "is what it is" in the US. A sport that, while attracting enough audience to be a professional league, will never come close to football, basketball or baseball - at least in our lifetime. At best, it can hope to get equal to hockey (which, I'd argue, it's fairly close right now).
How to say this,without tripping a bunch of PC landmines.
In this part of N.J.,pro soccer fans are,for the most part, either foreign born,or first generation Americans.
The only exception are some heavily Scottish or Irish areas,like Harrison/Kearney.
Local youth soccer programs are pretty much at capacity,but that doesn't translate to crowds at pro games.
There's also a big drop off in youth participation in soccer,as kids approach high school.
Seems that,once kids stop playing,they loose interest.
Around here people don't tend to follow college sports,so most kids grow up Giants or Jets not Redbull fans.
You're also talking about much smaller stadiums for pro soccer vs. pro football.