From the Daily Beast here:
In my opinion, the national anthem is a symbolic song about our country. It represents honoring the many brave men and women who sacrifice and have sacrificed their lives each and every single day to protect our freedom. Sitting or kneeling down during the national anthem is a disgrace to those people who have served and currently serve our country. Sitting down during the national anthem on September 11th is even more horrific. Protest all you want and use social media all you want.