I think even in Northern America people are more concious of the popularity of football worldwide.
I have yet to attend a MLS game myself in order to have an opinion about the football in the US but from the information I have, I do like the progress this game has done in United States.
By this I'm not talking about the impact of the almost retired superstars from Europe or similar arguments. I have seen that a kind of an ultras movement has risen in the United States. I got the impression that the fans of some of the teams like Seattle Sounders and Atlanta United are real football aficionados. The kind you would find in Europe or South America. And that is what makes the difference in football.
If they only would addopt a system which will enable promotion and relegation from the MLS, it would bring footbal in the states to a complete new level.