Image copyright Getty Images

Outside the courthouse in Brooklyn where the trial of the Fifa officials charged with corruption will take place is an all-weather football pitch crowded throughout the week with players of all ages.

Not far away, in Brooklyn Bridge Park, where once derelict piers have been converted into outdoor sports centres, the soccer pitches are usually more crowded than the basketball courts.

A short walk down the hill, an archway under the Manhattan Bridge last summer hosted one of New York's World Cup "viewing parties", where thousands gathered to watch games, and not just those involving the American national team.

So it seemed incongruous to stand in front of the courthouse last week, fielding questions from presenters in London about why a country with no interest in football had suddenly assumed the role of global policeman of the global game.

That line of inquiry seemed about a decade out of date. It is akin to the blanket condemnation that Americans lack a sense of humour or irony - this in the land of Jon Stewart, Tina Fey, Stephen Colbert, Chris Rock, Amy Poehler, Jerry Seinfeld, David Letterman and Garry Shandling.

Image copyright Getty Images Image caption The Seattle Sounders is America's most-watched soccer team

Polyglot nation

True, football, or soccer as it is known here, is not as central to American as it is to European, African or South and Central American life. Nowhere near.

Up until recently, the game has been unloved by the major US television networks, which have long bemoaned the lack of breaks in play, the paucity of goals and the glut of draws.

Absent from the US game are big-name male stars and big-name clubs. The New York Red Bulls will never rival the New York Yankees. Real Salt Lake pales, rather risibly, alongside Real Madrid.

However, football is no longer met with American indifference. Nor any more does it offer proof of America's sporting isolationism. In this polyglot nation, the game is growing in popularity and importance, an upward trend that will continue long into the future as America becomes less white and more Hispanic.

Already, America is the number one country in the world for youth participation in football. More than three million youngsters were registered to play in 2014, compared with just 103,432 in 1974.

Crowd puller

Major League Soccer matches now have a higher average attendance - 19,148 in 2014 - than basketball and ice hockey. The game ranks third after American football and baseball.

Image copyright Getty Images Image caption The average attendance at Sporting Kansas City was 20,000 last year

Though the crowds here are significantly smaller than in the Bundesliga in Germany, the Premier League in England and Wales, La Liga in Spain or Serie A in Italy, they are on average bigger than in Argentina, Brazil, China or the Football League Championship.

Average attendances in 2014-15

Bundesliga: 43,532

Premier League: 36,083

La Liga: 26,803

Serie A: 22,019

Major League Soccer (in 2014): 19,148

The Seattle Sounders, America's most-watched team, attracts larger crowds for home games than Everton, Tottenham, Aston Villa or even Chelsea.

The strength of the game in Seattle is also a measure of how its popularity extends well beyond the new immigrant hubs of New York, Chicago and Los Angeles.

Sporting Kansas City, in the American heartland, is also one of the better-supported sides.

Last year's World Cup in Brazil witnessed record viewing figures in America, even though the national team did not make it past the final 16.

And even after it exited the tournament, viewers kept tuning in - 29.2 million for the final between Germany and Argentina.

By comparison, that year's baseball world series attracted 13.5 million.

Nor is American enthusiasm for the World Cup a new phenomenon - more than 18 million people watched the 1994 final between Brazil and Italy - but it has been growing.

The average viewing figure for matches in last year's World Cup matches was 4.3 million, up 50% from 2010.

All those kids who grew up playing the game are now, as adults, watching it.

Soccer in the USA

Media playback is unsupported on your device Media caption Can a Liverpool-loving Brit find football fans in the US?

More video:

Soccer seen as ‘sissyball’ in Deep South

Why US soccer has no relegation

Do Native Americans play football?

Money spinner

Football in America also transcends the gender divide.

Of the kids playing the game, 48% are girls.

The USA has twice won Fifa's Women's World Cup, a record matched only by Germany.

Mia Hamm, who accumulated a staggering 275 caps and scored 158 international goals, has been called America's greatest female athlete of the past 40 years.

In terms of her marketability, Nike ranked her alongside Tiger Woods and Michael Jordan.

Image copyright Getty Images Image caption Mia Hamm represented the USA for 18 years, winning Olympic gold twice, in 1996 and 2004

It is also worth remembering that one of the most sought after demographics in American politics is the country's army of suburban "soccer moms."

The term is hardly new. It was coined in the mid-1990s.

Money is another indicator of the game's attractiveness.

NBC splashed out $240m (£160m) for the rights to Premier League football between 2013-16, three times more than Fox paid for the previous contract.

With a fierce bidding war now under way, the next deal is expected to dwarf that figure.

The wider availability of Premier League matches, which attract much bigger television audiences than domestic games, is also helping to raise the profile of the sport.

Gone are the days when diehard fans used to have to find bars open on a Saturday morning with satellite feeds beamed in from Europe.

Now every single Premier League game is available on cable. Ditto the FA Cup and Uefa Champions League.

On Univision, the American Spanish language network with viewing figures on a par with the major US networks, soccer, unsurprisingly, is the number one sport. Broadcasting live matches has fuelled the channel's rapid rise.

Image copyright Getty Images Image caption The USA reached the last 16 of last year's World Cup in Brazil

New 'Big Four'?

No longer do foreigners have to explain the intricacies of the offside rule to perplexed locals, or why games are allowed to finish in a tie (a draw).

Many Americans are now fully literate in the sport.

So while American soccer may never rival American football, the notion that it remains a niche sport is absurd.

Though gridiron, baseball, basketball and ice hockey are known here as the "Big Four" sports, soccer has surely ousted ice hockey to join that quartet.

It is the fourth most popular high school sport for boys, and the third for girls.

There are many reasons why the US Department of Justice mounted these prosecutions.

Two of those indicted, Jeffrey Webb and Chuck Blazer, were dominant figures in the American game.

Jack Warner, of Trinidad and Tobago, used to head up Concacaf, the Miami-based Confederation of North, Central America and Caribbean Association Football.

Prosecutors claim the alleged bribery scheme relied heavily on the US banking system.

But although the US authorities have also targeted foreign nationals, they do not regard soccer as a foreign sport.

Announcing the charges, FBI director James Comey stressed how American kids and others at the grassroots had been deprived of resources.

The FBI has cast a global dragnet, but this is also a homeland investigation.

The Fifa allegations dominated the media here last week, and, paradoxically, that marks another milestone in the game's recognition.

The game has moved from the back pages to the front.