A few months ago, thousands of Americans began experiencing the typical features of diehard nationalism coupled with uncharacteristic symptoms of World Cup fever.

While football fans in England opted to switch off the television rather than watch Steven Gerrard cry, Americans concluded their World Cup with tweets ode to hero goalkeeper Tim Howard, who made 16 saves in America’s 2-1 extra time loss to Belgium in the knockout phase. But then the World Cup ended, and Americans booked their flights home to the country that calls football soccer.

Still, while hundreds gathered at places like San Francisco’s Civic Center Plaza to watch America play Ghana on the big screen, some didn’t even pretend to like soccer, or the San Jose Earthquakes just miles away, when the World Cup isn’t around. “I’m kind of a classic band wagon follower”, Anthony Olund, 22, said. “I don’t watch soccer a ton. But I love to support the USA for everything”.

Others, like Maribel Gonzalez, 50, have been die-hard football fans since birth. She calls football “fútbol” not because she’s trying to be cool, but because she’s from Mexico. Since 1980, the US Hispanic population has grown from 14.6 million people to nearly 52 million as of 2011, according to the Census Bureau.

That’s dramatically changed the political and cultural landscape in America, and seen a huge rise in football fandom. “Today I’m here for the United States. That’s my team”, Gonzalez said during the match. “They’re doing better than expected. They might go far. If America played against Mexico, I don’t know who I would support. My heart would be torn”.

Fortunately, both Mexico and America were eliminated before it came to that. And Americans kept watching anyway. The World Cup Final between Germany and Argentina was the most-watched soccer match in US history, drawing more than 26 million viewers. The beautiful game’s popularity only falls behind baseball and American football in the United States.

Sara Conti and her whole family of football fans turned up to watch America play Ghana. “We’re all pretty big soccer fans. We grew up watching soccer. We pretty much go whenever we have a chance to go”, she said. “Chris Wondolowski is playing for the national team, which is really exciting, to cheer on a Bay Area native”.

Unlike England, where clubs are often dissuaded from buying home grown talent due to the premium price tags that accompany them in deference to ready-made foreign players – Southampton sold Luke Shaw to Manchester United for £30m, their captain Adam Lallana to Liverpool for £25m and promising defender Calum Chambers to Arsenal for £16m, an eye – MLS players are by and large drawn from the US. 31 year-old Wondolowski captains the San Jose Earthquakes, one of the ten founding members of the MLS in 1996.

Things have changed a lot since those early days, with 19 teams now contesting America’s premier division, attracting 43% more dedicated fans than just over a decade ago.

As a sign of the times, the Earthquakes and San Francisco’s American football team, the 49ers, have announced a partnership to reach out to those in the more lucrative, global football market, inviting teams like Manchester United to play in their stadiums. United, one of the most valuable sports teams in the world, is worth an estimated $2.8bn, compared to the Earthquakes $75m. But if football’s rise in America continues beyond the World Cup, this could well change, shifting the balance of footballing dynasties around the world.

Lew Glenn, whose son is a soccer player, was skeptical the World Cup would make much difference for America’s football fan base. “I think if the Americans do well, it helps. If they don’t do well, it probably doesn’t matter. We only pay attention if we win”, he said.

He wants all Americans to be just as passionate about soccer as he is. That’s why he’s a part of the San Jose Street team, a group dedicated to garnering more Earthquake fans. Glenn became an Earthquake fan himself ten years ago after a trip around Europe convinced him he was missing out on the most popular sport in the world.

“The fanaticism in Europe is amazing to me. The fact that it’s growing to that level here is amazing to me. Thumbs up all the way”, he said.

Only last week, the United States women’s team defeated Switzerland 4-1 in a friendly match. The top-ranked team in women’s international football, having twice won the Women’s World Cup in addition to their four Olympic gold medals, will shortly commence qualifying for the Women’s World Cup held in Canada next year. And if they could just find a way to capitalise on the rise of football fandom in America, maybe, just maybe, more Americans will come out to watch.