This was a case of straight-up dishonesty on the singer's part. It was admittedly pre-meditated, and she kept it secret from those who mistakenly honored her by requesting she sing the USA's national anthem. It was a purely pre-calculated political statement on her part, and thus completely in-appropriate in these circumstances. I suspect if she'd asked to sing both songs ahead of time, she may have very well been granted permission. As it stands, she was deliberately being devisive and dishonest, and should apologize.