I think she was so focused on jazzing up the tune, that she lost her place with the lyrics. And on the most watched U.S. TV program - ouch!
Usually hearing the Star Spangled Banner is a bit emotional for me. It is a reminder of how blessed I am to live in a democracy, and how a lot of people in the world still live in oppressive regimes, and how people had to get shot at and die and stuff, to create that democracy. But with her jazzing up the tune, it is so annoying that when I hear it I just want the song to end. Ugh.