I'd like to add something else that would add humor to it. This year, Bush celebrated Cinco de Mayo on the fourth of May! Maybe he did it on purposely, but it ruins the meaning of the name of the holiday, doesn't it? And one time when Bush went to France, he called one of the leaders, "amigo."
You wouldn't believe how many people I've heard say that Mexico's independence day is May 5. They're not just guessing, they're SURE that's what the holiday is. I'm just impressed he knew it, he doesn't seem like he's the best at getting his facts straight during speeches and interviews.
To add on to a previous comment a local singer where I live has a song about a ton of mistakes our President has made and if anyone would like to check it out the singer's name is John Macutchen
In response to what "me" said- that's the whole point of the quote. Bush was asked to translate "dieciseis de septiembre" and said that it meant September 15th. Dieciseis means 16, though, not 15. Numbers like that are pretty basic Spanish.