Don't worry; yes, he's only a troll but his words belie the typical insecurity that Americans have about their place in the world. They have their own sports like Baseball and "Foot"ball (that nobody else plays) because they have to be different from the rest of the world to re-inforce their "we are the best" image.
It's the same as their silly "spelling", their insistence on the absurd "system" for measurements, (distances, weights, volume...) and their absolutely braindead un-democratic governmental system, which has shown itself to be a farce.
BUT BUT BUT
There is a HUGE number of very well-educated, free-thinking, pro-choice, pragmatic and worldly people in the USA too, and they are the ones who suffer thanks to the behaviour of their asshole politicians and moronic christian-right idiots.
And for those who are interested, "Soccer" has more players that any other sport in the US, and its popularity is climbing rapidly. If it were true that 99% of Americans "don't care about the World Cup", why on >earth would ABC and ESPN be showing every game in HDTV? Why are the games being shown on at least three channels simultaneously? I think it'd be fair to say in reverse that the rest of the world couldn't give a shit about the "World" Series or the "Super" Bowl, two sporting events that are pretty sad and self-important.
Troll.