There was a time when American Football wasn't that popular here in the US.  It's only been a couple of decades since it's overtaken baseball as the most popular spectator sport.  I've been reading some articles that suggest the Super Bowl is the most watched sporting event in the world.  It seems hard to imagine that it's more popular than the FIFA World Cup title matches, but that's what I've been reading.

It's only been few years since Premier League Soccer has started to take a foothold in the US.  Before that the only televised soccer matches were found on the Hispanic stations, and focused on the Mexican, Central American, and South American leagues.  In general soccer still isn't very popular here.  I find myself among the few that care enough to pay attention.  I played football and soccer in high school, but focused on soccer in college.  It was by far my favorite sport to play, but that puts me in the minority on this side of the pond.

Even though I always enjoyed playing soccer more than any other sport, similarly I always enjoyed watching football more than any other.
 There's a lot of strategy to it.  It can be a complex game to understand, and certainly the toughness of the players is impressive.  They're more like Roman Gladiators than mere athletes, which is probably why I didn't like playing the sport as much as watching it, lol.