I'm just taking a dig at your dig
The world plays soccer, the US plays football. So unless you live in the US, you have no reason or opportunity to play US football to begin with. And if you live in the US, you have no reason to play soccer (although a lot of people do), so you play football. That's why I said it made no sense, but I know you were trying to play the all American football tough guy...lol

. Sports as a whole have nothing to do with being tough though, I think all sports are great, it's about the competition in the end.
And there are quite a few sports in the world that are about 100x tougher than American football. You named one, Rugby. So is Australian Rules Football.
And sorry, nothing is as tough as boxing. That one takes the cake (and you can lump all that UFC crap in there with it).