Chris Brown: Refuses to Stand for National Anthem ... On 9/11

Chris Brown joined the National Anthem protest Sunday -- the occasion was a charity basketball game ... and 9/11.

Tank, who sang America's song, urged the crowd -- even those who would otherwise protest -- to stand in honor of the 3,000 people who perished during 9/11. Brown, who planted himself on the hardwood, was immovable. He laughed with friends as people around him stood.