Differing opinions, but the current loudest American anti-football voice belongs to Dan Shaughnessy of the Boston Globe:

http://www.bostonglobe.com/sports/2014/06/21/soccer-doesn-get-kick-out/uTIF1VQ8QHOpfDyWI0W4KK/story.html?p1=ArticleTab_Article_

Today, he was also on an ESPN (sports channel) show called Outside The Lines, where he repeated his views. I can't find the video but here's excerpts of some of the conversation:

http://www.sbnation.com/soccer/2014/7/2/5865309/world-cup-2014-dan-shaughnessy-outside-the-lines

The country has seen record viewing figures:

http://www.independent.co.uk/sport/football/worldcup/world-cup-2014-soccer-becomes-the-second-most-popular-sport-in-the-usa-if-you-look-at-tv-figures-9576787.html

You also have the Amy Coulter's who believe the recent increase in soccer viewership is as a result of the "moral decay" of the society and due to immigration!
http://www.clarionledger.com/story/opinion/columnists/2014/06/25/coulter-growing-interest-soccer-sign-nations-moral-decay/11372137/

I believe in two decades football will have grown into one of the top 3 sports in the US. Behind American football and basketball.

I believe there is talent in this country that can be harnessed and make them a force to be reckoned with in International football. The American Football League - MLS (Major League Soccer) will improve, quality players will keep coming in, and I think they might be able to export some of their players into Europe on a more frequent basis which will only make the quality of their national team better.

I'm looking forward to it. And I'm happy about the awareness this World Cup seems to have sparked within the national consciousness.