Wow, is this still being debated? Oh well, here we go again I guess. The ref was completely correct in giving out that red. If other refs are not giving reds for worse offenses, they are the ones in the wrong... but aside from the first red of that match, I haven't seen any worse offenses yet in the matches I've watched (and I've only missed three so far).
Facts are simple: He did not hit the ball... not even close in fact. He hit the ancle studs first with a sliding tackle (This is not debatable anymore, not after the replays became available online. Just look at the frame I posted with the exact place marked with a red circle showing the point of contact). The tackle was dangerous as hell. And that, according to the FIFA guidelines, has to give a straight red. No ifs, no buts, just a red card. We are not misinterpreting the rules - you are.
And we also mostly happen to be not Americans, not Italians, and thus not biased. As said before, none of us have any vested interest in that game but the entertainment value (which was considerable), except for you - and the other Americans on this board... most of whom seem to agree with us. We even mostly agree the Americans played a great game. But the ref did not decide the outcome.