The richest football team in the world is Manchester United, which Forbes values at $1.9bn. The richest baseball team is the New York Yankees at $1.02 bn (they’re the team that makes those "NY" caps you see everywhere). The richest American Football team is the Washington Redskins with a value at $1.4 bn. Surprised? Well, American football is a big sport.

How big, you may ask. In the National Football League (NFL) 18 new stadiums have been built since 1990, more than one a year, and two more are expected by 2010 meaning more than half of the NFL’s 32 teams have new home grounds.

This year the average NFL team is worth $898m, 212% more than when Forbes began calculating team values eight years ago. In 2005, the average team posted $30.8m in operating income (earnings before interest, taxes, depreciation and amortization), as against $5.3m in 1997.

Annual national broadcasting fees for the NFL climbed to $87.5m per team. The current broadcasting deals with General Electric, News Corp., the Walt Disney Co. and Viacom will pay the league an average of more than $3bn annually over the next six years - more than Major League Baseball and the National Basketball Association will earn combined. There is even an NFL Network - the first cable and satellite network fully dedicated to the NFL and the sport of American football 24 hours a day, seven days a week.

So why is it that you don’t know anything about the grid-iron game?

You’ve probably heard of the Dallas Cowboys and the New York Giants, maybe even the Denver Broncos and you definitely know the Raiders. But you’re not quite sure where they’re from. But what about the Indianapolis Colts (the only team to start consecutive seasons 9-0) or the Buffalo Bills (who hold the record for consecutive Superbowl appearances)? How about naming me a player? If you play video games I bet you’ll have heard the name Madden, though you might never have played it.

The reason for this obscurity seems to be twofold. Firstly, American sports are quite insular, the NFL more so than the NBA or MLB (both of which have Canadian franchises). The game is even called “American football”. The set-up of the game is very American - time-outs, no injury time, stop-start play, and hype.

The American market for sports is so large that there is little need to “export” the game to the world. The league can continue to make fistfuls of money without ever having to screen a game in a foreign country. This is now changing. Regular-season NFL games are broadcast in countries as diverse as New Zealand, Iran and Brazil.

Last season the Arizona Cardinals decided to play one of their home games (against the San Francisco 49ers) in Mexico City. This turned out to be a great idea as 103,467 people showed up, setting an NFL regular-season attendance record. The NFL noticed this and has now drawn up a plan for the 2007 season where at least two regular-season games will be played outside the US (Canada, Mexico, England and Germany are the only countries currently on the list).

The NFL is hoping that exporting the game overseas will create larger fan bases for the teams and the game as a whole and bring in even more money. However, they need first to overcome the second barrier - misunderstanding.

A recent sports-news article about American football was followed by the presenter saying: “And now on to a real sport, Michael Campbell hit a three over par…” This example sums up how many people see American football, less of a sport than golf.

The casual observer sees a bunch of over-hyped, overly-muscular men in giant pads and helmets running at each other. Rugby fans especially see American football as “soft” or “fake”.

Of course, American football is an extremely hard physical sport. The best analogy I have ever heard is: Sprint 40 yards, get tackled by a 280lb body builder, jog back to where you started and repeat. The pads help the players to be able to get straight back up after hits that would flatten the average person. Perhaps a testament to the toughness of the game is the large number of injuries sustained by players even though they are wearing all that padding.

I’m not sure what the answer to this problem is. How do you make a sport popular? TV coverage is a start and the new fad of televised poker and darts tournaments has shown that consumers will watch whatever is on. All I know is that I’ll be glued to the screen every Sunday (or Monday given the time difference) cheering on the big guys, the big hits, the big runs and loving the big hype.