Answer:
It is a tradition in the United States to play "The Star-Spangled Banner", the national anthem, before sporting events. According to the United States Code, those present should stand at attention with right hand over heart." We chose to kneel because it's a respectful gesture. I remember thinking our posture was like a flag flown at half-mast to mark a tragedy." Some regard kneeling as disrespectful to those who have died or been wounded in service of the United States, such as police officers or military veterans.