I find it boring to watch other people play a game. I know one of my friends was very upset that Mexico lost and was out of the World Cup. I wish more people would root for the USA if they live here if they're going to root for any team at all.
I find this game, at this level, exciting and exhilarating. Now, I agree that Americans should root for USA and, most of them do. However people also have favorites for other national teams mostly due to 2 causes: 1) national origin. No doubt, and it is quite natural, Mexican-Americans and French-Americans are going to cheer their national team. 2) For the love of the game - simply enjoying and appreciating the style, the technique and the heart with which a particular team plays. Hence, many people are a cheering for Brazil or Germany or Dutch or Chili.
As for myself, I was rooting for USA and Italy. Both are out, so I will simply enjoy the game, perhaps leaning a bit more towards Netherlands or Germany. I tell you, this Friday match between Germany and France is going to be much more than a soccer game. It will be a national and world event. You have to travel outside of US to appreciate the enormous popularity of football/soccer.
We could only hope that Israel will make it to the next world cup. I tell, you, ayrabs will go crazy and and their birth rate, at least for a month, will drastically drop.