time for.....the INFAMOUS DEVIL'S ADVOCATE HAT! *dun dun dunnnnn*
First of all, the United States does NOT have an official national language (at least not according to all the references I've ever seen). There has never been a national language declared because of the United States' unique "melting pot" status, and the fact that we are a nation of immigrants.
What's wrong with the national anthem in Spanish? How is that a slap in the face? It's the same lyrics, same tune, same patriotic meaning. If it helps spread American patriotism and national pride to the non-English speaking Americans, I'm all for it.
Don't get me wrong. I think residents of this country should learn English, since that's the most popular language at this time. But I see nothing wrong with Spanish-speaking people taking in American patriotism in a way they can understand.
I also agree with Buckshot. It's sad how many Americans can't sing the lyrics properly, but they get mad at someone else not "honoring the anthem properly".