American football is an incredibly complex and nuanced game. I sincerely believe that is the only reason it isn't more popular world-wide. I think that the people who frequent this forum in particular could come to really love the sport simply because of the strategy of it. Indeed, famed Ohio State University coach Woody Hayes, a WW2 veteran, conceived of his play schemes in terms of classic military strategy and maneuver.
Let me see if I can put the game in terms all of you can appreciate-- Medieval Total War. Let's take the defensive squad of a football team:
The defensive linemen (the big guys with one hand in the dirt) are like your spearmen units-- they clog things up and maintain the front line where it is, and try not to allow any holes to form in the front.
The Linebackers (the slightly smaller-- if you can call 250 lbs. of muscle and bone small-- guys standing behind the defensive linement): these guys are like your swordsman units-- these guys fill any holes that open up in your defensive front, or are used as "blitzers," attacking either up the middle or around the flank to get to the ball carrier.
The defensive backs-- the smallest and fastest guys on the defense, these are your cavalry (you can even break it down into light (cornerbacks) and heavy (safeties) cavalry). Extremely fast and athletic, these are your playmakers (or breakers, as the case may be). Sending one of these guys on a blitz at the proper time can completely blow up a play. Also, their mobility allows them to protect the flanks and fill holes quickly to slow down an advance while reinforcements are en route, but you can't expect them to slog it out in the trenches all the time.
Of course, the exact responsibilities of the different positions vary with each team, scheme, and situation, but you get the idea. This is just the defensive side of the ball, and I didn't even get into pass coverages. Modern NFL offenses are even more complex, and teams vary greatly in their philosophies and strategies; for example, the St. Louis Rams are like a Muslim faction in MTW (emphasizing speed and precision to strike at the opponent quickly and decisively), while a "smashmouth" offense like the Pittsburgh Steelers is more like a Catholic Faction (using brute force to gradually grind the opponent into submission).
Anyway, American football is something you really have to learn about to appreciate in any capacity beyond enjoying the chili-cheese dip at the Super Bowl party. Once you do understand it more fully, I think you'll realize why it's by far the most popular sport in the U.S.
This is not to say that Soccer isn't great as well. I love soccer, and I can't wait for the World Cup. It's just that... well... American football is better.
By the way, the collisions in the NFL are essentially like getting into a 30 mph care wreck-- without the car. Those guys would die if they weren't wearing pads.
FYI: the reference to 300+ pound men running a certain distance in sub-5 seconds is to the 40 yard dash. "The forty" has become the standard measure of a football player's speed. If someone is said to run a 4.4 forty, that means they run the 40 yard dash in 4.4 seconds (extraordinarely fast). I don't think I could run a sub-5 second 40 at a slender 160 lbs, so for a 300 pound behemoth to do it is impressive indeed.
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